Freshwater Aquarium Setup - Fish Tank Setup

This freshwater aquarium setup article explains how to set up a basic freshwater fish tank. We'll start with a short list of the equipment you'll need and then give you a step by step guide on setting up or starting your first freshwater fish tank.

Freshwater Aquarium Setup

Aquarium Equipment Checklist:

STEP 1: Realize the responsibility involved.

Learning how to set up a fish tank is not all that difficult, but there are some steps you should follow for a freshwater aquarium setup.

First, you must realize a few things about an aquarium setup. A tropical fish tank is just like having a dog or a cat when it comes to the amount of effort on your part. In order to have a successful freshwater tropical fish tank you will have to work at it. It is also prudent to research any of the live animals you are planning to keep to limit the impact our hobby has on freshwater fish conservation.

Once a week, or at most once every two weeks, you will need to perform some kind of maintenance on the tank. Most of the time you will be performing water changes. You will also have to feed your fish at least once a day.

Setting up and running a fish tank does cost money. There are recurring expenses such as replacing filter media, buying food, etc. Check out the Freshwater vs. Saltwater Aquarium page to get an idea of the setup costs involved. If you are up to the challenge, please proceed!

STEP 2: Decide on which fish to keep and on aquarium size.

It's a good idea to have in mind what kind of freshwater fish you want to keep before you purchase an aquarium.

Some fish only grow to be an inch or two, whereas other types of tropical fish can grow 12 or 13 inches or more in length! Knowing what kind of fish you want will help you decide the size of the tank they will need. If this is your first time with an aquarium, it may be a good idea to start with a 10 or 20 gallon aquarium setup for now and stock it with some smaller and hardier species.

To get your creative juices flowing, research freshwater aquarium setup ideas by checking out the Freshwater Aquarium Builds forum to see how members have set up their aquariums.

Below are some of the more popular freshwater fish species that are also commonly available either locally or online.

STEP 3: Decide on the aquarium's location.

Place your freshwater aquarium setup in an area where the light and temperature of the tank won't be affected by external sources such as windows and heater vents.

Sunlight that enters the room through an unshaded window could affect the temperature of your tank. This could also lead to green algae problems for your tank down the road. You will want to place your aquarium on a stand that will be able to hold its total weight.

You also want to be sure that the floor is able to support the total weight of the aquarium and stand. A good rule of thumb for determining the total weight of a full aquarium is 10 pounds per gallon of water. For example, a 55-gallon tank will weigh approximately 550 pounds when filled with water!

STEP 4: Buy your aquarium and equipment.

Now is a good time to decide on the type of aquarium filter you will want to use. You will also need to purchase a heater capable of heating the freshwater aquarium setup size you have.

The Cobalt Neo-Therm Heaters are a popular choice for heaters these days. Buy the gravel, plants, a power strip and other decorations. A good rule of thumb for the amount of gravel that you will need is 1 to 1.5 pounds of gravel per gallon of water. I'd recommend getting more natural looking river type gravel versus the neon colored gravel you see in stores. The natural gravel will look nicer long term.

Another consideration is whether or not you want to make it a planted freshwater aquarium setup. If so, you will want to invest in some higher output lighting than what normally comes with all in one freshwater aquarium kits.

STEP 5: Set up your aquarium and stand.

Wash out your tank with water only! Do not use soap or detergents. Soap residue left behind will be harmful for your tropical fish. If you are going to use an under gravel filter (not recommended) now would be the time to set it up as well.

STEP 6: Wash Gravel, plants and decorations.

Be sure to wash the gravel thoroughly before adding it to your tank. An easy way to do this is to put some of the rocks in a pasta strainer and wash them out in your bath tub. Then place the clean gravel in a clean 5-gallon bucket for transport to the aquarium. After adding the gravel you can place your plants and decorations.

STEP 7: Add water to the aquarium.

To avoid messing up your gravel and plants, you can place a plate or saucer in the middle of your aquarium and direct the water flow onto the plate.

Use room temperature water when filling. To remove the chlorine and chloramine, use something like Tetra AquaSafe for Aquariums. Don't completely fill up the aquarium until you are sure of the layout of your decorations. Otherwise, when you place your arm in to move stuff around water is going to spill over. Doh!

STEP 8: Set up equipment.

Install your heater but don't plug it in until thermostat in the heater has adjusted to the water temperature. This usually takes about 15 minutes or so. Hook up your filter and any other equipment you have, then top off the aquarium water in your freshwater aquarium setup to just under the hood lip.

Place your hood and tank light on the aquarium and then check your power cords to be sure that they are free of water. I would also recommend using a drip loop on all of the power cords to be extra cautious. For more information on safety, read this great article on aquarium electrical safety. Plug all of the equipment into a power strip and then "turn on" the aquarium.

STEP 9. Wait, wait, wait and then wait some more.

I know, you want to add some fish. But, in order to do this right you must wait until your aquarium has cycled before adding any fish. Cycling is the process of growing beneficial bacteria in your aquarium to process harmful fish wastes.

There are ways of speeding up this process. Check out the nitrogen cycle page to learn more about starting the nitrogen cycle and how to speed it up. If you must use fish to cycle, try to get a hardier species like the zebra danio or cherry barb. You may notice your fish tank cycle kicking in gear if you start to get some cloudy aquarium water after a few days.

STEP 10. Add tropical fish.

Only add one or two fish at a time. Adding a couple fish at a time gives your filtration system the time needed to take on the increased biological load that the new fish introduce.

When you bring the fish home let the bag float in the tank for about 15 minutes so that the fish can become acclimated to the temperature and pH of the aquarium water.

After 5 minutes of floating the bag you should add some of the aquarium water to the bag so that the fish can become acclimated to the pH level in the aquarium. This will help reduce the amount of stress imposed on the fish. Stressed fish often leads to dead or diseased fish!

Don't feed your fish on the first day. They probably wouldn't eat any food on the first day anyway. Let them get acquainted with their new home.

If you're interested in some good and hardy first fish, please read the Good First Tropical Fish article.

STEP 11. Get ready for regular maintenance.

Be prepared to spend some time once every week or two to clean your tank. Performing regular water changes will reduce the nitrates level and keep your tropical fish happy and healthy.

As you can see, the steps for how to set up a fish tank are not that complex and hopefully you now have your aquarium setup and running! Have fun, take care of and enjoy your fish!

There are many ways to set up a freshwater aquarium. Here is a quick video showing another way to set up a tank.


Freshwater Aquarium Setup Comments

From: Julie Stafford - Cloudy Aquarium Water
We have had a tank for about a month with fish in it. The water all of a sudden turned cloudy last night and has continued that way today. Is this a normal transition process of newer tanks or is it a problem?
Response: Cloudy aquarium water in a newly established tank could be attributed to a few different factors:
  • Overfeeding - try to feed your fish very tiny amounts and only give them as much as they can consume within a minute or two.

  • Bacterial Bloom - If your cloudy aquarium water is a cloudy white or gray you may be experiencing a bacterial bloom. This bacteria is talked about on the aquarium nitrogen cycle page. The aquarium nitrogen cycle is an essential cycle that you should definitely know about. Please read the article.

  • Completely replacing filter media - if you change out all of the filter media when you perform your tank maintenance you are removing most of the beneficial bacteria mentioned above and may be causing your tank to go through a mini-cycle. Try to swap out only half of the filter media during maintenance. power filter sometimes come with two filter slots just for this purpose.

  • Water Changes - if you recently did a water change sometimes the water coming out of the tap can be cloudy. To avoid this (and some other potential problems, such as pH swings) it can be a good idea to let your water age a day or two before using it in your water change.

If we had to guess as to what is currently causing your cloudy water it would probably be the bacterial bloom since you mentioned that your tank is only a month old. Get an aquarium water test kit and monitor your water parameters throughout the nitrogen cycle.


From: Lee
I just wanted to say thank you for this website. We are very new to this fish thing (got the tank, got it cycling... no fish yet on the advise of LFS) but it's nice to read up as much info as we can before we actually get some fish!

From: Visitor - Adding Schooling Fish
We would like to add a group of schooling fish, 6 or more to our 100 gallon tank. I've read they should be of same size & age to school. How does this work with the "Add only two fish at a time rule"?
Response: Well, that's not really a rule, but a guideline to go by. The reason for slowly stocking your tank is so that you give your aquarium's biological filter time to catch up with the increased bio load that the new fish introduce to the tank. Having a 100 gallon tank, you should be fine adding a small group (6) of schooling fish such as neon tetras, or glowlight tetras or any of the other smaller sized schooling fish. This is assuming your tank is not overstocked and you have compatible tank mates for smaller fish.

From: William - Fish Overcrowding Question
I just got started this past month and have taken my time and I believe gotten things right. I started with a 10 gallon tank and now that I have chosen what types of fish to stock... the smaller varieties, I was needing to know at what point does one stop adding new fish? What's optimum for not overcrowding. I poked around the net and haven't found any real answer. Is there a gallon to small fish ratio or something I can use as a guideline?
Response: Many places will tell you the 1 inch of fish per 1 gallon of water rule, but this rule or guideline is ridiculous. Would a 10 inch pleco be ok in a 10 gallon tank? Of course not. A better rule of thumb would be 1 inch of fish for every 3 or 4 gallons of water (this is a freshwater guideline only, saltwater fish need even more water) with even more water volume per inch being better.
It really comes down to how often you will be performing water changes. Be realistic with yourself. Are you really going to stick with regular water changes every couple of days in an overstocked tank, week in and week out? If you answer no to this question then you definitely need to go very light on the stocking levels in your fish tank.
You're really limited with what you can do successfully in a 10 gallon tank and urge you to resist the temptation to overcrowd your fishes. One last thing, always use the future adult size of the fish when determining the potential stocking levels for your fish tank.

From: Mathew Schultz - Aquarium Lighting
Hello, I am a brand new fish tank owner, I bought the fish tank for my 2 year old daughter as a christmas gift. Your website has been a great help to me. I do, however, have a question I need an answer to that I can't find on your website. Does the tank light need to be turned on 24 hours per day, or do I turn it off at night? Thank you for your time, and once again, your website has been a great help to me.
Response: Thanks for the compliment on the site and welcome to fish keeping! Fish need to rest just like us and will appreciate some down time with the lights off. A good range of time to keep the lights on for a fish-only setup would be 6 to 10 hours per day. More information on fish tank light.

From: Greg - Algae Problem
I have a 72 gallon bowfront, I had a 30 gallon long that I moved the gravel, water and fish. The tank was perfect for about 3 weeks, 2 water changes. Now its a sort of hazy greenish color. I suspect an algae bloom because of the long light hours, but wanted to make sure without going the chemical route. I've read that too many chemicals is just as bad as none, purists preferring only to dechloronate. Please advise. The fish seem very hungry and happy so they don't seem stressed and no smell.
Response: Try to cut down on the amount of nutrients in the tank by cutting back on the amount of food that enters the tank, removing some fish if overstocked, and/or changing foods if the foods you're using are high in phosphates. Keep up with the partial water changes on a regular basis (weekly) during Aquarium Maintenance and shorten the photo period to about 8 hours per day and see if the situation clears up. Try this route before taking the chemical route. Using more chemicals than necessary is only treating the symptoms (green water) and not the root cause (high nutrient levels) and you would have to continually do this to keep your tank looking nice. Please try the non-chemical route first.

From: James S. - Overstocked Tank?
My name is James and I am somewhat of a beginner at owning an aquarium. I have been around them from time to time but have never officially owned one, so even my basic knowledge is not broad. I have a 55 gallon tank with 2 Oscar's, 2 Bala sharks, 1 Pleco, an Iridescent shark and I believe a black tetra (the cat fish and the tetra came with the tank). I want to first make sure that my feeding is done correctly as well as tank care. I have been feeding twice a day with one Oscar on goldfish and the other on pellets, unless he feels like a fish and there is one small enough for him, the rest get flakes and I drop two shrimp pellets for the Iridescent. I feed the second time with pellets for both the Oscars and bloodworm's for all (the Oscars will partake as well) and more shrimp pellets for the Iridescent and an algae wafer for the Pleco. Is this a good plan or should I change it up somewhere? It seems to be going well but i don't know how much of the flakes are getting eaten before they dissolve, they devour the worms though. I think the Pleco is also eating some of the shrimp and the Iridescent goes after the wafer a little too.

I have only owned this tank for two weeks and have done one cleaning. I have read a lot of info from your site and have come up with this so far. My cleaning schedule is 20 percent every two weeks with a filter rinsing. My main filter is a canister with 4 levels of media, I change the white fine filter media (I believe it to be filter floss, it came with the purchase and I haven't had to buy more yet) every change. I am looking at changing the carbon every other water change, but I don't know when I should change the ceramic. My instruction say to only change one part at a time but I wanted to get some more advice before my next cleaning. I also believe that the last owner did not change the water all that often, he left some in when I bought it to keep the bacteria alive. When I changed the fine media it was pretty dark and when I was gravel cleaning there seemed to be a lot of debris and crud. My water is still somewhat cloudy and I have started running a second back mounted canister filter for a duration to try to clear it up. I have been testing the water every week and there are no abnormal readings, the water does seem to be a little hard but some I have found that comes with living here.

Should I clean more often? There doesn't seem to be any immediate problems and I just wanted to see if you all had some advice and what I could do about the cloudiness? Thank you for your time and you have a very informative and excellent website.
Response: Hi James. While it may not seem like it now, the adult size of the fish you currently have makes your tank way over stocked. These fish will not lead good lives and will be living in increasingly bad water conditions as they grow larger. Here are some links to read up on these species:

Common Pleco can grow to be 12 to 18 inches as adults
Iridescent Shark can get up to 47 inches
Oscar Fish can get up to 12 inches
Bala Shark can get up to 13 inches
Black Skirt Tetra Is this your tetra? It stays quite small and won't last long in your tank.

You need to take back the iridescent shark, the tetra and the bala sharks. You could potentially keep two oscars in a 55 gallon tank but you'll need to keep a rigorous maintenance routine in the form of frequent large water changes. The iridescent gets way to big for most home aquariums and the bala sharks like to have alot of swimming room and may not do that great with oscars. It sounds like you have some pretty good filtration and it should be fine for 2 oscars, but you will need to stay on top of the water changes.

The cloudy aquarium water could be from the amount of food entering the tank, the fish waste and a bacteria bloom which is usually the sign that the Aquarium Nitrogen Cycle is starting. You'll need to get a good Master Aquarium Test Kit that tests for ph, ammonia, nitrite and nitrates (at minimum) and monitor your water frequently during the cycling process.

As far as filter maintenance goes, it wouldn't be a bad idea to change the white filter floss or at least rinse it well in discarded tank water every week or every two weeks. You should never need to replace the ceramic rings since they are the place where the good bacteria grow and this bacteria is what helps keep the ammonia and nitrites in check. You'll be removing the nitrates via the frequent water changes. The carbon could be replaced once a month or so.

So, our advice would be to take back the iridescent shark, the tetra and the bala sharks and get a refund or store credit. Keep the oscars since they are great fish with tons of personality with the stipulation that you will be staying on top of those water changes and filter maintenance.

From: Mark - New Tank Syndrome
I have bought a 3 and 1/2 foot tank with light and filters. Poured some tap water and added some pebbles. Then went to an aquarium and bought some good looking fish (nearly 25 of them). Dropped them into the tank and saw that every day at least a few fish die. This tank water colour also changed to a gloomy grey colour. Then I have decided to surf the net and found that I have missed the aquarium nitrogen cycle and to remove the clorine.
Now what can I do to prevent further death and to ensure that my tank is healthy?
Response: The first thing you should do is try to take back most of the fish that are still alive to the fish store and ask them to hold them for you while you cycle your tank. A good fish store should help you out here. Then get a master aquarium test kit which is usually cheaper than buying the test kits individually. If you still have some fish in your tank, test your water frequently (daily or a few times per week) and perform partial water changes as needed to lower the ammonia and nitrites in the water. Cycling with fish can take longer than doing it fishless for this very reason. You don't want your fish to die so you have to perform those water changes, but those water changes are prolonging the time required for your filter and tank to complete the cycle since you're removing most of the ammonia and nitrites via the water changes. Please read the nitrogen cycle page for ideas on how to speed up this process and for doing it fishless.

From: Lizzie - Upgrading to a bigger tank and Fish Transfer
Hello, I have bought a second hand tank which is bigger than my other tank. It is three foot wide and fifteen inches tall. I have, already established, a two and a half foot tank which contains a large pleco fish (about 12" long). I would like to know how to ensure that this new tank is disease free and how to transfer the pleco without harming him. I assume that I will move the water from the old tank to the new, but how much extra water can I add without diluting it too much. Someone said to clean the new tank with bleach and ensure it is rinsed well. Is this right? I really would appreciate your help as we are attached to this fish and would hate to harm him. Thank you.
Response: Hi Lizzie - Glad to hear that you're getting a bigger tank for your Pleco. If we're talking about a common pleco, it's still on the small side if we calculated correctly (approximately 30 gallons)? Using bleach to clean the new tank is not really necessary. If this aquarium had fish in it before, simply rinse it out thoroughly and wipe down the inside walls with just water. Do not use soap or chemicals. You can use some of the old water if you like and it might help the cycle in a small way, but be sure to keep the old tank's filter media floss to use in the new tank's filter. Also put some of gravel from the smaller tank in some old pantyhose (for easy removal later) and place it in the new tank. These two items, the floss and gravel, from your old tank will help you get your aquarium cycle started in the new tank.

Once everything is up and running for a few weeks and the cycle has completed, slowly acclimate fish to your new tank.

From: Denisia - Dieing Fish
My boyfriend just bought me swordtails. This was about two and a half weeks ago and since then every single fish has died in my tank with the exception of my sucker fish and my catfish. They all started swimming backwards and upside down. What happened?
Response: Wow. This is a totally open ended question that will be difficult to answer without much more information. When posting tank questions it is extremely helpful to post your water parameters along with the question. Include things such as the temperature, pH, ammonia, nitrite, nitrate, age of the aquarium, tank size, filter used, etc. The more details, the better.

Is this a new tank setup? If so, do you know about the aquarium nitrogen cycle? If it is an established tank, did you quarantine your swordtails before introducing them to your display tank? If not, they could have had a disease that could have been the reason for the tank wipe out. Are you using an undergravel filter and did you recently do a large water change? Aggressive gravel vaccuming can be harmful if harmful gas pockets that sometimes form under UGF plates are released into the tank. Any large infusion of new water with drastically different water parameters (pH, temp) can be equally harmful. Sorry for the lack of any answer but there are too many unknown variables here.

From: Lance - Goldfish with Tropical Fish?
I have a 30 gallon tank, my fish all do well in the tank. My daugthers have a goldfish in a 1.5 gallon tank. No matter how often we clean the tank the water turns orange. We want to move the goldfish the larger tank but we are afraid that he could have something that might harm the other fish, what could that be and do you think he'll be fine with the other fish?
Response: Goldfish are heavy waste producers and need a larger and well filtered tank. preferably at least 10 gallons per goldfish and even more gallons per fish for larger goldfish. Mixing them in with tropical fish may not be a good idea since goldfish do better at slightly cooler temperatures than tropicals. It's good that you want to move your goldfish to a larger tank but it would be better to get it a larger tank of it's own that can be kept cooler (around 70°F).

From: Carter K. - Stocking Levels
I was wondering if this setup would work: 10-12 tiger barbs, 2 clown loaches and a red tailed shark. I was planning on keeping these fish in at least a 29 gallon tank (the 29 being a last resort) it will have some sort of cave along with some live floating plants (any recomendations?). There will be either very fine gravel or some sort of sand. I do not know the filter or heater type I will get yet. Do you think these fish would do okay in this setup?
Response: A 29 gallon fish tank is too small for an adult Clown Loach. The clown loach can get up to 12 inches (30 cm). Please use the adult size of the fish you want to keep to determine the tank size you'll need. As far as compatibility goes among these species, this mix of fish should be able to be kept together in a much bigger tank. Glad to read that you're researching before buying though. Kudos to you.

From: Marcus - Cloudy Water in New Aquarium
I have just setup a new freshwater aquarium, and for the first 2 days it was very clear and clean, but now I have been adding a little bit of fish food every 12 hours and it has gotten a little cloudy. Is this usual and is there any way I can get rid of or stop this from happening?
Response: Yes, this is normal and indicative of a bacterial bloom at the onset of the nitrogen cycle. More info here: cloudy aquarium water.

From: Jim Prochnow - Need way more information
My grandson has a 10-gallon tank with 4 danios, 2 swordtails, a 3 female guppies. We have had 3 male guppies die in succession within the first 1-2 weeks of being introduced to the tank. All the other fish remain healthy. I'm at a loss.
Response: That was too many fish for a 10 gallon tank. You're most likely at your limit since the death of the 3 male guppies. We do need way more information before we could guess as to what the problem(s) is/are. We need info such as water parameter readings for ammonia, nitrite, nitrate, pH, temperature, etc. Has the tank cycled? How long has the tank been set up? Is their good surface agitation for gas exchange at the surface so that oxygen levels can remain at adequate levels? How often do you perform water changes? What type of aquarium filter are you using? How were these fish acclimated and what are you feeding them? Etc, etc.

From: Kelly - Purpose of Aquarium Filter
The purpose of the filter is to remove large particles from the water right? So does it have to run 24-7? Is there another purpose for the filter? Thanks for all your help. This forum has been a huge resource for myself and my kids.
Response: The mechanical aquarium filter is designed to remove larger particles via the filter media (floss). You do need to leave it running 24/7 to keep the materials trapped in the filter floss from quickly rotting. If you did run it only periodically, you'd have to change out the filter materials after turning off the filter and then insert new materials before starting it again. The mechanical filter can also aid in gas exchange and you could also use activated carbon to remove dissolved organics from the water which will help keep the water looking and smelling clean. In fact, most replacement media for power filter for instance, have activated carbon inserted in the middle of the filter floss. Remember to change it (or at least rinse it with discarded tank water) periodically. Neglecting to do so will lead to nitrate problems down the road.

For our power filters, we like to buy the cheap Filter Fiber (filter floss) and make our own replacement filters. We replace our power filter floss frequently and use the cheap stuff. About the only time we don't is when we need to use activated carbon and then we sometimes use the regular filter sleeves, since they are better designed to hold in the carbon. But you can also buy the mesh bags for using activated carbon in your filter. Old pantyhose works too.

From: Becky - Stocking question
I've just bought a 10 gallon tank that I'm currently cycling. I just want to keep some neon tetras in a shoal. How many do you think I could keep in that size tank? This site has been invaluable to me for setting up my tank so thank you.
Response: If that's all you're going to keep in the tank, a group of 5 to 7 should do fine. The neon tetra is a great fish, lots of activity and beautiful colors. They've been getting a bad rap lately for not being as hardy as they once were. Take your time when acclimating them to your aquarium. Try the slow drip method of acclimation with these fish to lessen the stress levels when introducing to your aquarium. Thanks for letting us know the website helped you. Always glad to hear that, thank you.

From: Kristine with a compliment
Thank-you, Thank-you. Your web site is the best. The information is very good and I've learned so much. This is my first freshwater/live plant aquarium and at first it scared the beans out of me. But I'm cool with it now. Thank-you
Response: Excellent to hear, glad to be able to help. Thank you for the comment.

From: Jack Smith - Fish Compatibility
Hi - I love your website and I recommend it to all my mates. I was wondering if you can put a siamese fighting fish in with a few neon tetras if they werent too cramped.
Response: If you have a filter, heater and big enough aquarium for housing these fish then you shouldn't have problems with this stocking scheme. The betta (siamese fighter) should stay towards the top of the tank whereas the neon tetra will stay in the middle to lower levels. For tetras, the neons are very peaceful but many people (even veteran fish keepers) are having problems keeping neons. They use to have a very hardy reputation but that seems not to be the case nowadays. Keep up with the water changes and keep the nitrate levels on the low side.

From: Gina - New Fish Tank Questions
Hi! We just bought a 48 gallon tank and were instructed by the store owner to wait 5 days with the power filter running before we bring in the fish. We had the water tested before we placed the fish in and we must say we are a bit confused with what to do now after reading all this information on this amazing site. If all the readings on the water were safe/normal do we still have to do regular testing? Did that mean that our cylce stage already passed?

Our tank is white cloudy, so should we do the 25 percent water removal and less food step next? Also, we have 3 tropical fish and one goldfish. The tropical fish have all picked corners and hideouts and rarely move. My concern is feeding. When we try to feed the tropical fish, the goldfish swims around and eats everything up before they get a chance to. Hes not aggressive but we end up overfeeding the goldfish because we keep trying to put food in for the other fish to have. They are all around the same size as well. Should we return him? Is there a trick for feeding greedy fish?

Next question is that one of our tropical fish is a dalmation fish and he has planted himself behind the heater in the corner. He does not move much and is pressed up against the heater. Is it bad for the fish to be that close? Is that normal behavior? Does is mean that he is cold? Thank you for your help!
Response: Unless you're using something like bio-spira or an established filter, 5 days is too soon to consider a tank cycled. The white cloudy water is most likely indicative of a bacteria bloom. Please read or re-read about the "aquarium nitrogen cycle". To increase the chances that your current fish survive you'll need to perform frequent partial water changes throughout the cycle or better yet, try to get your hands on some bio-spira or filter media from an established tank. Once your tank is cycled and assuming you improve your water quality throughout the process the fish should go after the food. You definitely don't want to overfeed here as it will only make the water problems worse.

Goldfish can be very hardy and the water quality issues may not be affecting it like the tropical fish. Goldfish are heavy waste producers, different water requirements and I wouldn't mix the two. The dalmation fish sounds like a Molly? Depending on the temperature of the tank, it could be cold or just stressed and looking for someplace to hide.

Good luck with your aquarium. It sounds like you were given some questionable advice by the store owner. This does indeed make it harder for those just starting out and is bad business.

From: Taylor H. - Fish dropping like flies
I recently bought a 10 gallon tank for my daughters birthday, and being a first timer I bought the fish along with it, took it home filled it up, added some aquasafe and threw in the fish! It's now 3 days later and my fish (I bought 18!) are dropping (well floating) like flies! Needless to say my daughter is quite unhappy and I guess I can only hope a few survive the cycling now that I know why the fish are dying in my white cloudy tank. I guess in a few weeks I can replace a few fish. They should really tell you about this cycling at the store! Thanks so much for all the info, at least now I know what is going on.
Response: A good store will mention the aquarium cycle, especially if they know you're new to the hobby and they wouldn't have let you purchase so many fish for a 10 gallon tank. We as hobbyists though need to be proactive in our research efforts beforehand as well. A fish tank can provide some good bonding and educational opportunities for you and your child. Good luck with your new tank and have fun learning about this great hobby.

From: Geoff - Too many fish in tank
I have recently purchased a red bellied pacu and I placed him in the tank and he swam very erratically and is currently hanging at the bottom. He bashes his head into the wall, is not eating and is an all around crazy fish. So I have quarantined him and would like to know what to do. In the tank he was in it was 2.5 feet long 2 feet tall and 1.5 feet wide. I know it is too small for him and I would love to buy him a new tank but I am young and currently low on cash for now. All ph levels are normal, same with temperature and all the other good stuff. He is about 4 inches and his tank mates are a giant danio 3.5 inches, a tinfoil barb which is the same size, 3 penguin tetras and 2 rosy barbs that are 2 inches and 1 pleco about 3.5 inches. Please help!
Response: You need to check more than just the pH and water temperature in your tank. You also need to check ammonia, nitrite and nitrates at a minimum. You have way to many fish for this aquarium. Some of these will get way too big for it, such as the Red Belly Pacu, the Tinfoil Barb and the Pleco. You'll need to return these fish for store credit, get a much larger tank or give them away in order for them to have a quality life. Please research the fish before buying them and read up on the freshwater articles in the beginner's section which is linked in the left navigation under Beginner's Guides.

From: Jodi - Cloudy Aquarium Water after water change
I have 50 gallon column freshwater tank that has been set up for 5 months. 2 balas, 4 clown loaches, 2 silver dollars, 2 dojo loaches and 4 zebras. I have a Fluval 450 also. How can I prevent the water from getting cloudy after a water change? It is crystal clear beforehand.
Response: Hmmm, maybe you could use a filter on your faucet to filter the replacement water before adding it to your tank or even let the replacement water sit for a couple of hours to let the gases dissipate. It's worth a try and those faucet filters are really inexpensive. Just an FYI - your tank is overstocked and will lead to problems down the road, sooner rather than later. The Balas and clown loaches can get quite large.

From: Barb - Smelly Aquarium
Question - I have a 29 gallon tank which has been going for 2.5 years, the home of community fish. I have recently added 3 Rummy Nose and 3 tetras but the tank is not overcrowded. The water is clear, the tank is clean, but it has recently developed a very "fishy" odor. Any suggestions? Thanks.
Response: Try using activated carbon in your aquarium filter. Or, if you are running activated carbon, replace it if it's been awhile. Activated Carbon should do the trick, along with regular partial water changes and gravel vacuuming.

From: Bob - Forgot to Rinse Aquarium Gravel
Hey great web site. The wife and I are on it at least once a day! We recently purchased a 46 gallon bow front fish tank for the house and I forgot to wash off the gravel before filling the tank. I am planning on buying an aquarium vacuum tomorrow to clean it up and I was wondering if this would be a problem. I looked all over the web site but found nothing on any accidents like that. I don't really want to drain the tank so hopefully a vacuum will do it? Thanks keep up the good work.
Response: Hi Bob. Although I'd love to take the credit, what makes this place so great are all of the forum members here. It's always fun and interesting. As far as rinsing the gravel goes, I'd get that gravel vacuum (python vacs are great) and give the gravel a couple of thorough vacuuming sessions. How many really depends on what type of rock you're using. If it's the colored small pieces you may be at it awhile. If it is larger pebbles maybe a couple of vacs should do it. Also, don't forget to read up on the aquarium nitrogen cycle before adding any fish.

From: Mike from Alaska - Getting Friend's Fish
I have a friend who needs to take down his aquarium setup for a couple of months while he redoes his flooring. He's curious about the process (should he wash and reuse the rocks when he sets up again? Will anything grow on the bio filter wheels while they sit dormant? Soap and water okay for everything?) He has offered me his small collection of fish - is there anything I should test for before importing them into my tank?
Response: Hi Mike - tell him that he can definitely wash the rocks in just tap water, no soap. It can be difficult to remove all of the soap residue and it would be harmful for the fish if he were to reuse that gravel. Things may grow if the bio wheel while it sits dormant, but probably nothing that would help the fish. He hee. What if you took his filter and hooked it up to yours and left it running until he can set his tank up again? This is assuming that he didn't have any sort of pest problem or disease issues with his fish. Assuming that you could take it off his tank and on yours rather quickly, the beneficial bacteria in the filter should be able to make the transition to your tank. This way your friend wouldn't have to re-cycle his tank when he set it back up.

Test his tank parameters (pH, general hardness, nitrates) and then test your tank parameters to determine the differences in readings. This should give you a good indication of how long to take when acclimating these fish to your aquarium or quarantine tank. The quarantine tank would be the best way to do it if you feel that you need to monitor them before introducing to your main aquarium.


From: Kabir - New Tank, Fish Deaths
I have a new 25 gallon aquarium with lots of fish in it, like different types of angelfish, various goldfish, catfish, black widow tetras, silver dollars, betta, guppy, pleco, loach etc. I have a problem and that is the aquarium is cloudy and a couple of fishes are dyeing frequently too.

Now I am planning to get a 50 gallon tank because I suspect that the water in my 25 gallon tank isn't good for my fish. The question is whether I should transfer some water from my 25 gallon tank to my 50 gallon tank because I plan to transfer some fish to the new tank also. What should I do? By the way, I can't find the water testing kits in my locality. Any other way to test the water?

Response: That is a lot of fish for a 25 gallon aquarium. I'm glad to hear you're upgrading to a 50 gallon tank. Read up on the "aquarium nitrogen cycle" since it's likely that your tank is cycling which is leading the death of your fishes. If you can't get test kits locally, you'll just have to wait out the cycle which can take up to 2 months starting from scratch all the while performing frequent partial water changes to keep your fish from dying. If you can, increase the aeration and tank temperature, then get some of a friend's old filtration media and use it in your filter to help speed up the process. More ideas on how to speed up the cycle on the page mentioned.

From: Stacey - New Tank (not cycled) Stocked with Fish
I recently inherited a 30 gallon tank, filled it with water and let the filter run for 24 hours and then went off to the pet store to buy 11 fish! I feel ridiculous now that I know about the cycle (oddly, the staff sold me 11 fish as well as the recommended bottle of Cycle). However, the fish seem happy on day 2 but I know it will be tough. I have 2 yoyo loaches, 4 black tetras, 1 gold gourami, 1 pearl gourami and 3 emerald corydoras which I know now will be a little overcrowded eventually. Do you think I will be able to maintain this many fish in this size tank? All are still relatively small but I am worried that I may have doomed them.
So far my water is cloudy but I have added lots of Cycle and I did a 10 percent water change on day 2 and the fish perked right up.
My big question is how can I make the cycle process less stressful now that I have introduced my fish too soon? Thank you! Your site has been a wake up call.
Response: Yeah, unfortunately some pet stores don't ask any questions, they just want to do their jobs, make the sale and go home. You could try to take most of the fish back until the cycle has completed. I've heard both good and bad reviews on the product you're using. Most members on the forum here really like the bio-spira product for cycling new tanks.
If for some reason you can't return the fish, you will have to stay on top of the water parameter testing for ammonia, nitrites and eventually nitrates. As you know from reading about the cycle, ammonia and nitrites can be very harmful to your fish and you'll need to keep these parameters very diluted in order for your fish to make it through the cycle. Partial water changes are the best thing you can do for your fish right now. The downside to doing all these water changes during the cycle is that it may lengthen the amount of time it takes to finish the cycle. Cycling with fish is the hard and long way to do it. Re-read the cycle page for ideas on how to speed up the process.

From: Jim Harris - Hard Water Deposits
I just got a 55 gallon tank from a friend and it has a lot of (hard water) build up. I was wondering what is the best process to fix this. Thanks I really enjoy your site.
Response: Hi Jim - assuming this is an empty tank you're cleaning, try a 50/50 vinegar/water solution in a spray bottle. Spray it on, let it sit for a few minutes and then scrub with a wash rag or towel. Rinse and repeat. Be sure to rinse the tank well with clean water to remove any remaining vinegar from the tank glass. We have to do this on the quartz sleeves of the aquarium uv sterilizers. We just let the quartz sleeve soak in this solution for about 10 minutes and then wipe off the deposits. Works like a charm.

From: DONL121 - How many fish? - Stocking question
What is the equation for figuring out how many fish to put in a tank. I have a 39 gallon high tank. I have 4 gold gouramis, 2 red parrots, 1 gold severum, 1 red rainbow, 2 giant danios, 1 pleco and 1 catfish. I'm looking to add an angel or 2. Thanks for the help.
Response: There isn't an "equation" to compute an exact figure for the amount of fish you can keep in an aquarium. It boils down to fish temperament, water surface area for gas exchange, tank size and shape, etc. A tall tank like yours will be able to hold less dissolved oxygen in the water due to it's smaller amount of surface area at the top of the tank for gas exhange. Sorry to say but your tank is already way overstocked when you take into account all the adult sizes of these fish.
Please do not follow the 1 inch of fish per 1 gallon of water rule! This "rule" only works for the smallest of fish species. Also use the adult size of the fish when considering them for your aquarium.

From: Kingsley - Stocking and aquarium filter question
Hello, my name is Kingsley and I am a beginner. I have a 55 gallon tank with 1 Iridescent Shark and 2 oscars. I want to know if these fish are perfect for the tank size and if I should always leave the power filter on 24/7?
Response: Hi Kingsley - you definitely need to keep the aquarium filter running 24/7. Also remember to rinse out the filter media on a regular basis, especially stocked as you are... The Iridescent shark is going to be way to big for a 55 gallon tank. Return it to the store for a credit or refund. The two Oscars should be ok in a 55 but would be better in a larger tank.

From: Brock - New 29 gallon setup
I just purchased a 29 Gallon tank, got a kit with it that included filter and water heater and the rest. Washed the rocks, cleaned my ornaments, and put in the water heater. I just wanted to know would it be a good idea to add a live plant in the tank to help the nitro cycle? I plan on adding columbian sharks to the tank when its well and ready. Also how many columbian sharks would be proper for a 29 Gallon. 1 more question, is a 100W water heater enough for a 29 Gallon?
Response: I'd hold off on plants until after the cycle has completed. There will be more nutrients available from the fish (nitrates) once the cycle has completed. The columbian shark gets way too big for a 29 gallon aquarium. So, don't add any to your tank please. A 100 watt heater for your 29 gallon sounds about right.

From: Ryan
Thank you fishlore! This website has helped so much over the past few months and we use it a fair few times a day! Once again thank you!
Response: Awesome! Very glad to hear that and just glad we could help you. We hope you get as much enjoyment out of this great hobby as we do.

From: John E. - New Tank and Overstocked
My girlfriend just bought me a 10 gallon tank. I wanted to start out small because of the skills needed to keep up. Anyway, the tank came with a filter, heater, hood with the light. I bought some salt and water conditioner. I rinsed out every thing. Then I added two tablespoons of salt and two caps of conditioner. I then let it sit for 24 hours (supposed to be 48 at least) but I got kinda fish happy and decided to buy some. I figured-water temperature is stable between 78 and 82 degrees F, so I got 2 bala sharks and 2 clown loaches. After a couple of hours the water got a little cloudy, for some reason I feel like something isn't right. Oh and I found out that my girl fed them without me knowing on the first day and I heard that you weren't supposed to. I really don't want to hurt these little guys and I really like my new fish. So if there is something I could do while I buy a 100 gallon tank (But not for like a couple (2) months) I'd apreciate it if you could let me know. Thank you for reading!
Response: Sounds like you have read up on the Bala Shark and the Clown Loach after getting them and now realize the large tank accomodations they really need, with a 10 gallon being way too small for them. The cloudiness could be from a bacterial bloom which usually indicates that the aquarium cycle is kicking in gear. As the fish release wastes into the tank bacteria spring into action to start converting the ammonia into nitrites and then nitrates. Find the aquarium nitrogen cycle article here on Fishlore for all the details. I'd return these fish to the store for store credit. Let the store know where you bought them from that you only have a 10 gallon tank. They should have asked what kind of tank they were going in anyway. If they don't take them back I'd shop elsewhere in the future. Until you can get them back to the store perform partial water changes (about 25 percent) daily to keep the fish from perishing. Then save up for a larger tank or shop for smaller species to stock the 10 gallon tank. Read up on the beginner articles here to get up to speed. It's not difficult at all, just takes a little diligence on your part.

From: Mervyn W. - Aquarium in Bedroom?
Can a tropical fish tank be placed in a bedroom. I have one in my 12 year old son's bedroom and was wondering if it is safe to do so for health reasons.
Response: If your son has immune system problems you should know that there are bacterial infections that aquarists can catch from aquariums. Our aquariums are loaded with bacteria (good and bad) and it's always a good idea to use sleeve length gloves (Aqua Gloves) when working inside the tank. There are fish species that can be harmful (venomous species like the saltwater lionfish, rabbitfish, etc.) too. Check out this article too: Fish Diseases Transmitted to Humans.
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From: Jeff R. in Arizona - Reuse old tank water in new tank?
I'm cleaning my 30 gallon cube tank and have the fish and the water into a 10 gallon tank while I clean and change the gravel. How many gallons of the old water should I save to put in the new tank. I'm also planning on seeding it with some of the old gravel as well as keep the current filter media intact for about a week before changing. Comments on this method for redoing my larger tank?
Response: Hi Jeff - it's likely that your gravel and filter media will contain the bulk of bacteria needed to carry on the cycle for your new tank. Personally, since you're using some gravel and filter media from the 10 gallon I would start with all new water in the 30 gallon. Make sure that you keep the filter running on the old tank while you are preparing the new tank. Otherwise, the beneficial bacteria could die off if the filter is turned off.

From: Momo - Thanks
I just wanted to say thanks for making this article! It really helped when I got my first tank, (29 gallon). It provided me with the extra info that the fish store didn't give me. Especially about the cloudy water!

From: Vicki - Tetra Safe Start
I have a 55 gallon tank, new set up. It has 1 pearl gourami, 1 dwarf gourami and 6 platy. Used Safe Start to help boost the cycle. My question is how long before my ammonia levels start spiking? Currently we are on day 5 and ammonia and nitrite levels are 0, nitrates at 20. Thank you in advance, great informational site.
Response: According to the information on this product the ammonia and nitrites may be quickly converted to nitrates in the first day or two. So, you may not see any ammonia or nitrite spikes when using Tetra Safe Start. Sounds like many folks are getting good results using it too.

From: Jack C. - Fishkeeping tips
I have been in the fish hobby for more than two decades and now do volunteer work at the National Aquarium in Baltimore. I hate to see empty aquariums, with stories about how we tried but all the fish died. I believe that a lot of hobbyists are doomed from the start from pet dealers who care more about making a sale than the welfare of the animal. For example I've heard retailers telling customers they can add their fish the same day they purchase their aquarium although some may survive it is generally a bad idea and a good way to set yourself up for problems down the road. I've also heard retailers speak about catfish replacing a filter. Another false statement is fish will only grow to the size of their environment. That is only partly true. Mostly confining a large fish to a small tank is simply cruel as well as buying a juvenile and not being prepared when it reaches it's adult size. My advice to you is do your homework know what you want before buying on impulse. I don't buy livestock from large chain stores. There's to much going on to do everything well. With a little research you should be able to find a fish only store. Most important read and do your research before all else. Remember slow and steady will be rewarded with a life time of aquatic enjoyment.
Response: Good points. Thanks for sharing your tips.
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