Saltwater Aquarium Setup Guide

This step by step guide is for anyone interested in learning how to set up a saltwater aquarium. A saltwater aquarium doesn't have to be difficult.

It just takes some effort on your part to learn about and research the necessary topics in order to have a good saltwater setup. Let's get in to it.

Saltwater Aquarium Setup

What do I need to start a saltwater aquarium?

For the type of saltwater fish tank setup (marine aquarium) described in this article check out the checklist below for the equipment needed.

Saltwater Fish Profiles
saltwater fish profiles

Realize the responsibility, time and costs involved

A saltwater aquarium setup is just like having a dog or a cat when it comes to the amount of effort on your part. You really need to be sure that a saltwater fish tank is right for you before diving in. There are lots of factors to consider.

In order to have a successful saltwater aquarium you will have to work at it. On a daily basis you will need to feed your fish and monitor the water parameters (temperature, nitrates, etc) and some of the aquarium equipment on your saltwater setup. Once a week, or at most once every month, you will need to perform some kind of aquarium maintenance on your fish tank. Most of the time you will be performing water changes and water quality testing. Future up-keep tasks are an important thing to consider. Do you have time in your weekly schedule to stay on top of these tasks?

Cost is another very serious factor. Take the list above and research the prices of the various equipment needed to setup a saltwater fish tank. You will soon realize that a saltwater aquarium can cost significantly more to purchase than a freshwater aquarium setup. Not to mention that saltwater fish are usually more expensive that their freshwater counterparts.

You also need to understand that setting up a saltwater aquarium takes time. It often takes 4 to 8 weeks before you can add any marine fish safely to your saltwater aquarium setup.

Read, read and then read some more

There are many great saltwater books out there and we've reviewed a few of them. Some of the better saltwater books are:

The Conscientious Marine Aquarist,
The Complete Book of the Marine Aquarium,
Saltwater Aquariums for Dummies,
Reef Secrets,
Simple Guide to Mini-Reef Aquariums,
Complete Encyclopedia of the Saltwater Aquarium,
Marine Fishes, 500 Essential to Know Aquarium Species, and
The New Marine Aquarium.

There is also a ton of information online on saltwater fish. Do yourself a huge favor by reading as much as you can before you invest any money in your aquarium equipment and fish. You'll be glad you did. To get a general idea of how much it costs to setup a saltwater aquarium, check out the Freshwater vs. Saltwater Aquarium page for more info.

Decide on an aquarium size and location

It's a good idea to know what kind of saltwater fish you want to keep before you purchase your aquarium. Do a lot of research on the various types of marine fish to determine which fish you would like to get. Some marine fish only grow to be an inch or two, whereas other types can grow to 12 or 18 inches! Knowing what kind of marine fish you want will help you decide the size of the aquarium they will need.

Below are some of the most poopular saltwater fish species profiles here on FishLore. Read them to get an idea on the proper aquarium size to get started with.

Many books stress that you shouldn't get started in the saltwater hobby unless you have at least a 40 gallon. But if you've done your research and thoroughly prepared, there is no reason why you can't start with a smaller tank. Be warned, a smaller tank will pose more challenges and will force you to perform more frequent water testing and maintenance.

You will want to place your aquarium in an area where the light and temperature of the tank won't be affected by external sources such as windows and heater vents. You will also want to place your aquarium on a stand that will be able to hold its total weight. 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 only! You also have to account for the total amount of live rock, sand and equipment.

Saltwater Aquarium

Buy your aquarium and equipment

Sometimes you can find some really deals on complete saltwater aquarium kits whereas other times it is better to buy the equipment individually. Now is the time to decide on the type of filtration you will want to use when you setup your saltwater aquarium and the type of protein skimmer. We do not recommend using an undergravel filter. An undergravel filter is not needed and will only cause you headaches down the road. Since we will be using live rock as our biological filter, you really only need a modest filter for the mechanical and chemical filtration. Don't skimp on the protein skimmer. After the live rock, the protein skimmer is probably the next most important piece of equipment. When it comes to protein skimmers you really do get what you pay for. We have posted a few protein skimmer reviews and there are many more out there. Listed below are skimmers that we have reviewed:

Octopus 800s Protein Skimmer - *Very good skimmer
Octopus 200 NW Protein Skimmer Review - *Very good skimmer
AquaC Remora Protein Skimmer - *Very good
Tunze Nano Protein Skimmer - *Very good
Hydor Slim Skim Protein Skimmer - *Ok skimmer
Red Sea Prizm Protein Skimmer - *Ok, needs frequent adjustments
Fission Nano Protein Skimmer - *Don't waste your money
Visi-Jet-PS Protein Skimmer - *Don't waste your money

You will also need to purchase a heater capable of heating the aquarium size you have.

Get the live rock, sand and a power strip. Try to get 1 to 2 pounds of live rock per aquarium gallon. One rule of thumb for the amount of sand that you will need is about 1/2 to 1 pound of sand per gallon of water. Don't use sandbox or playground sand because it can have various unknown particles that may be harmful to your fish. Get either live sand or an aragonite based sand (from caribsea) or crushed coral.

A recent development in the past year or so has been biopellets. These are small polymer based bio-degradable pellets (biopellets) that as they slowly break down in your reactor will begin to feed and grow bacteria that will consume nitrates and phosphates thereby lessening the growth of undesirable algae forms your tank. You have to use a skimmer to get the full benefit of using biopellets and you need to direct the flow from the pellet reactor into the skimmer so that the excess "gunk" (or whatever the waste products of the pellets is called) is skimmed out of the system. Setting up a biopellet reactor will set you back about $100 dollars or so but it is well worth it, especially if you are fighting algae problems in your display tank. For more information or to get started, check out the biopellet article.

Set up your aquarium, stand and equipment

Wash out your tank with water only! Do not use soap or detergents. Soap residue left behind will be harmful for your saltwater fish. Smoke test your aquarium by filling it with fresh water and check for leaks. If it passes the leak test, drain the fresh water from the aquarium.

Affix your background at this time. Be sure to use tape all across the top back of the background to prevent any salt creep from getting in between the background and tank glass. Alternatively, you can also paint the back tank glass (paint the outside back, not the inside). Painting the back glass can be better than using a background because you won't have to worry about salt creep making its way in between your aquarium background and the back glass. For marine tanks, a black background can help the fish colors stand out more. Deep blue is another popular color choice and it can help create the illusion of depth. After painting, let the tank sit for a day or so to allow the paint to dry.

Install your heater, hook up your filter, protein skimmer and any other equipment you have and be sure to use a drip loop on all of the power cords. For more safety tips, read the aquarium electrical safety article. Don't plug in anything yet!

Add pre-mixed saltwater to the aquarium

All of the marine salt mixes out there are made slightly differently. There is much debate as to which salt mix is the best. Here is a comparison on some of the available saltwater mixes. Unless you're considering a reef tank, most of the commonly available mixes should serve you fine. You'll soon develop a salt mix preference after you've worked with them for a while.

Use a clean 5-gallon bucket to mix the saltwater. First fill the bucket and then remove the chlorine and chloramine. Use something like Tetra AquaSafe for Aquariums. Read the directions on the salt mix package carefully and then add the salt mix slowly to room temperature water. Stir it well and test it with your hydrometer or refractometer. Once you get a specific gravity reading between 1.021 and 1.024 you can add the saltwater to your aquarium. Repeat this process until you have filled your tank. If you have a large aquarium you can mix the salt in the tank. Mixing in the tank can be more difficult and messy, so just be sure that you have thoroughly dissolved all of the salt mix before using the hydrometer.

Turn on the aquarium and let the water circulate for a day or two.

Cure the live rock

Live Rock Live Rock

Live rock is probably going to be the greatest expense with the initial setup of a saltwater aquarium. For a reef tank setup it may be the aquarium lighting. For this reason, you are probably going to treat your live rock like gold once you get it. However, even though it can cost a lot of money, it will probably end up saving you money (in fish) because it is the best form of biological filtration. The curing process can last anywhere from 1 week to 2 months or more depending on the shape the rock is in when you get it.

Drain some of the aquarium water and then place your live rock in the tank. Try to place it in the middle of the tank and aim the power heads (you should have 2 or 3) at the live rock. Placing the live rock in the middle of the tank will allow you to siphon up the debris that the power heads will be blowing off.

Every few days turn off the power to the tank so you can perform live rock maintenance. Use some new rubber kitchen type gloves while doing this to protect your hands and the rock. You will need to scrub the live rock with a brush that has plastic bristles (old tooth brush) to remove any obviously dead or dying organisms. You can do this directly in the tank. Siphon up the debris and then refill with pre-mixed saltwater. The day before you perform the live rock maintenance get your saltwater ready. If you have a smaller tank you can use a couple of 5-gallon buckets for this purpose. If you have a larger tank you may want to invest in a large rubber trash can for pre-mixing your saltwater. Whatever you use, you will need to place a power head and a heater in the pre-mix container so that the mix dissolves correctly. Test your water throughout the curing process to determine if the tank is cycling.

During the curing process your tank may smell pretty bad and a good indication that your live rock is cured is when it no longer smells bad but more like the ocean. Use your test kits to verify that the tank has indeed cycled. You should have 0 ammonia, 0 nitrite and some sort of reading on the nitrates.

Add your substrate

First, drain some of the saltwater in your aquarium to allow for the sand you're about to add and turn off the power to the tank. We'll use the 5-gallon bucket to clean the sand. Use the 5-gallon bucket to pre-mix about 2 gallons of saltwater. Add your sand to the bucket and then stir. This will allow some of the dust and dirt to rise so you can then siphon it off. Drain some of the saltwater from the bucket before adding your substrate. Use a plastic cup, ladle or something similar to add the freshly cleaned substrate to your aquarium. Use one of your power heads to blow off any sand that gets on your live rock during this process.

Allow the tank to settle for a few days

Monitor your water parameters closely during this time. Check the salinity or specific gravity, pH, ammonia, nitrite, nitrate and carbonate hardness levels and correct as necessary. Ideally, you want the following readings for your saltwater tests before you start adding fish to your saltwater aquarium setup:

Slowly add saltwater fish after the tank has cycled

I can't stress enough the need to use a quarantine tank for any new marine fish. You are playing a game that you will eventually lose by adding fish directly into the main tank. For more information on using a quarantine tank, please read How To Setup A Quarantine Tank.

Only add one or two saltwater fish at a time. Only adding a couple saltwater fish at a time gives your filtration system the time needed to take on the increased biological load that the new fish introduce. When bringing home new saltwater fish, the acclimation process is a little more involved. Dump the bag contents (fish and water) into a clean 5-gallon bucket and then add about 1 cup of aquarium water to the 5 gallon bucket every 10 minutes. Continue to add 1 cup of aquarium water to the 5-gallon bucket every 10 minutes. After an hour or so your marine fish or invertebrate should be ready to add to the aquarium (qt tank). Following this more involved acclimation process will help reduce the amount of stress imposed on the saltwater fish. Stressed fish often leads to dead fish! Don't feed your saltwater 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.

Perform Regular Aquarium Maintenance.

Be prepared to spend some time every day to monitor the temperature and salinity levels on your newly setup marine aquarium. You will also need to spend some time once a month to clean your tank and change out some of the saltwater. Try to change 20% of the saltwater in a given month. This could work out to doing small 5% water changes once a week. Performing regular small water changes will reduce the nitrate levels, replenish elements that have been used up and skimmed off and keep your saltwater fish happy and healthy. Remember to never add freshly mixed saltwater to your aquarium because it is fairly caustic freshly mixed. Mix it up the day before you will be doing maintenance.

Saltwater Aquarium with Live Rock

Below is a quick video on setting up a Saltwater Aquarium.

Saltwater Aquarium Setup Comments, Tips and Questions

From: Marc M. - Lowering salinity, specific gravity
If my Hydrometer is higher than the normal range its suppose to be in, what do I do?
If your reading is higher than you want it to be, the easiest way to lower the salt levels in the water is to perform a small partial water change with de-chlorinated freshwater only. Over time you'll get better at measuring the amount to use when pre-mixing the saltwater, it just takes practice. Also, it's good to point out here that whenever you need to replace evaporated tank water you should use de-chlorinated freshwater. Monitor the specific gravity on a weekly basis or at least once every two weeks.

From: Cori - Is a Reverse Osmosis Filter necessary?
Do you need to invest in a reverse osmosis filtration system to ensure that the chlorine and chloramines are taken out of the water? Would a sink mounted sytem like Pur or Brita work?
I know that the Pur ultimate will remove chlorine and chloramine but not sure on the Brita. The only way to be sure is to test the filtered water for chlorine and chloramine. If you plan on having a fish only setup, then a reverse osmosis system may not be necessary. If you are wanting a reef type system with corals and anemones then you may need to invest in a RO unit. It really depends on your tap water quality and the amount of impurities in it.

From: Oscar - Filter Followup
In response to Cori, if you intend to use a sink mounted system please bear in mind that they are designed to work at mains pressure. I adapted one of these filters for cleaning large aquariums but there was no way of providing the necessary pressure to work an ionisation filter.

From: Gordie - Is a sump or refugium necessary?
I've been researching on several sites, all of which suggest using a sump/refugium. Is this necessary, or can I save a few bucks by just using the aquarium and quarantine tank?
A sump or refugium is not mandatory for a fish only tank or a fish only with live rock (fowlr). However, they are definitely positive additions if you can afford them because they can be used to hide equipment, help in nutrient export and for the culturing of live foods for your marine animals. They also help promote more stable water parameters because sumps can increase the amount of total water in a salwater tank setup. You often will see marine setups that seem to be way overstocked but you can almost guarantee that there is a sump equalling the size of the display tank hidden somewhere.

From: Paul - Live Rock Die Off
I have just set up a new tank 2 weeks ago. I have live rock, it has crabs and other living things (go figure) I have been told that these will die as part of the cycling process, is this true? Can I keep them alive?
It all depends on the shape the live rock is in when you start the aquarium cycle. If it's in good shape and was kept relatively wet or even semi-cured before you got it, then many of the living organisms may make it. If it's in bad shape from the get go and you are essentially curing it right now, then many of the life forms won't make it through the cycling process. However, marine invertebrates seem to handle ammonia and nitrite buildups better than saltwater fish and you may get lucky and have a few survive the cycling process.

From: Brett - Cloudy Water and is a UV sterilizer necessary?
I just set up a 55 Gallon tank recently. Started the filtration, added the substrate and salt water. However it is still pretty cloudy. Is there anything I can do to change that? Also, I was told my cycle starts now even though I don't have my protein skimmer in. I also heard something about a UV sterilizer. Mine is a fish only system. Is this necessary?
The water will usually be cloudy for a day, maybe 2 or 3 days at most. This is most likely dust from the sand that should settle or get filtered by your mechanical filter (i.e. power filter or canister filter, if you have one). If you had live rock (assuming you don't, since you say "fish only") in the tank already then the cycle may be started, finished or at some stage in between. It really depends on the shape the rock is in when you get it. If it's in bad shape you may have some serious ammonia spikes for the next week or so followed by nitrite spikes. We really encourage the use of live rock because it can be a great biological filter for your saltwater aquarium.

If you're not using live rock or live sand, then you have to add either fish or some other source of ammonia to the tank in order to get the aquarium cycle started. Please read the article on the aquarium nitrogen cycle for more information and tips. The protein skimmer has nothing to do with starting the cycle. The protein skimmer helps by removing the organic substances from the tank water before they get converted to ammonia, nitrite, nitrate, etc. They also help by increasing the amount of dissolved oxygen in the tank water.

In a fish only aquarium setup, the UV sterilizer is not really needed in our opinion. If you practice proper fish quarantine and fish acclimation procedures and keep your water parameters within acceptable ranges should never really need one of these devices. However, if you're keeping more expensive or delicate or hard to keep fish species it may be worth looking into. These units can be very expensive.

From: Sean - Live Rock Curing
I am going to get fully cured live rock. My question is, once it has been shipped over won't there be die off, creating an uncured peice of live rock? Thanks - Sean
If you're having it shipped to your home, then yes, there will most likely be some die off during the shipping process. You could sort of classify this type of rock as semi-cured. Some of the beneficial life will most likely make it through the shipping process but you will still need to cure rock of this kind in a separate tank or bucket for a few weeks before placing it into an existing saltwater setup. For more information, check out the live rock page.

From: Scott Douglas - Live Sand or Live Rock First?
I was wondering when you first set up a saltwater tank, if you can put the sand in first and then the live rock to cure?
You could do this but beware of a couple of potential problems. The first one is the amount of detritus, dead organisms and other matter that falls off the rock as it cures can be significant. It really depends on the shape the rock is in to begin with. If the rock has been curing in the dealer's tank for a few weeks and you take it home and put it in your new marine setup, you may not see very much detritus around the base of the rock.
Another potential problem is the danger from sand burrowing organisms becoming crushed under the rock as it settles into the tunnels created by these burrowing creatures and sometimes burrowing fish. This could also lead to instability of the rock scape as the base of the rock settles into the sand causing the top most pieces of the structure to hit the tank sides or even worse, cracking the tank glass. We like to place ours directly on the tank glass bottom and then put the sand around the rock for these reasons.

From: Chad - Cleaning a Saltwater Tank
Let me say first, thank you for this page. I went to the pet store today looking for a Betta and came out desperately wanting a saltwater fish tank. After reading this, I just have a couple questions. How do I clean the tank after everything is added? Will I need to take every single thing out? What if I have Coral or Reef?
As far as aquarium maintenance goes, if you follow our directions for the saltwater aquarium setup with live rock, you really are only doing small partial water changes and every once in a while you may have to do some light sand vacuuming to remove any darker detritus from the sand bed. The water changes are removing any nitrates that have built up since the last water change and you're introducing many needed nutrients and minerals (via the salt mix) that have been used up during the normal course of running your marine aquarium. You may also need clean the protein skimmer collection cup, clean any salt creep from the top of the tank and scrape the front viewing panel to remove any coralline algae build up. If you have a glass tank, check out the article on the DIY Algae Scraper.
You definitely don't want to be messing too much with the aquascaping in the tank once it is in place.

From: JMB - Start up water
I am setting up a 400 gallon saltwater tank and am wondering if it's ok to use chlorinated water to fill the tank up initially if I use a dechlorinator. Otherwise, how do you get the saltwater mix with freshwater in a tank that size?
Yes, it should be fine to mix the salt directly in a tank full of dechlorinated tap water. Mix slowly and test frequently with your hydrometer (or refractometer). Put a little less salt in than what is recommended on the bag/box. Let the mixed saltwater sit and aerate for a couple of days and then re-measure with the hydrometer to see how much you need to add. Don't forget to get the temperature up to normal operating temperatures before testing specific gravity. Lather, rinse and repeat.

From: John - Maximum Fish Load
Im setting up a 55 Gallon tank and I'm putting live rock, fish and invertebrates in it. If I put about 38 pounds of live rock in the tank, what is the maximum number of fish and invertebrates I can put in this tank? Thank you
Wow, this is a very open ended question... It all depends on what strikes your fancy. If you're interested in the blue chromis or green chromis, you can stock the tank with several and maybe have a small dwarf angelfish as the centerpiece of the tank. You can keep multiple skunk cleaner shrimp in the same tank. We could go on and on here. It really does depend on what you want to keep. Certain species may or may not get along. Larger fish species could make snacks out of your invertebrates, etc.
If you're looking for a "inch per gallon" rule or "4 inches of fish per gallon" rule, you're not going to get one here. There are just too many variables that need to be taken into account when stocking a saltwater aquarium.

From: Mary R. - Reef Tank Mechanical Filtration
Hello, I have learned a lot from your site but have a question about filtration. I have a 55 gallon tank that I am going to start a salt water reef system combining fish, live rock and different types of corals (not sure yet). If I am going to run a Cascade 700 filter do I also need another filter such as a Millennium 3000 Filter? There is so much reading involved which is cool but I need to make sure I am doing this right. Can you help me?
Thanks, Mary
Hi Mary - Good news, you really don't need those high tech mechanical aquarium filters when running a reef tank setup. Live rock and a protein skimmer are all you really need. You can always plug in the >canister filter if you want to run activated carbon (to polish the water) or some sort of phosphate removing media. You can step it up a bit by implementing a plumbed refugium and sump. While the addition of a sump and refugium are great enhancements, they are not mandatory for running a reef tank.
When planning and researching on how to setup your reef tank you'll hopefully learn about the importance of the lighting system. These high output (metal halides, T5-HO's) aquarium lights can get expensive and it would be better to use some of the money that you were going to spend on the mechanical filters and put it towards better lighting. It's excellent to hear that you are researching before buying your equipment and livestock.

From: Scott - Losing Fish - Need way more info
I have a cycled 55 gallon saltwater tank with 55 lbs live rock and 60 lbs live sand, all levels are fine but have loss the two first fish added to the tank. Can anyone help. The temperature is 78.
I know you say that "all levels are fine" but to the rest of us that means nothing. Always give the exact readings from test kits when asking for help. Ammonia, nitrite, Nitrate, Temp, pH, and others if applicable. Were the fish quarantined beforehand? Were they eating in the dealer's tank? Did they show any signs of disease? Need way more info before we could hazard a guess here.

From: Scott - New Setup
I have just finished viewing your website and I wanted to say thank you for all of this great info. It will be two weeks tomorrow 5/26/08 that I set up a 46 gallon bow front salt water tank. Sadly I was unaware about how cruel it was to use damsels to start to cycle my tank and bought six of them to do the job. I have a friend that is going to be giving a Clown fish and a yellow tang in a couple of months. My temperature is at 80 deg. and I tested my water today and my ph was at approximately 8.2, ammonia was 0, nitrite at 0.1. I used live sand also and currently going to be getting some live rock for my tank, I hope tomorrow if I can. Is there anything that I'm doing wrong or could be doing better? What should I do to make my tank good for the new fish coming. I will be returning the damsels before they come. Thanks for your input!
In our opinion you'll see better results if you get at least 45 pounds of live rock (1 pound per gallon, if not more), a protein skimmer and some power heads for water movement in your new marine fish tank. Keep the rock in your new tank for a couple of weeks and monitor for signs of ammonia and nitrites... Note that you may not see any of these levels if the rock has been in the dealer's tank for awhile. If that's the case you could slowly start stocking this tank. Get a protein skimmer if you don't already have one, take your time, go slowly, and research all fish before you buy them.

From: Kelly C. - live rock and new tank startup
A word to the wise, do not buy any rock from a dealer that doesn't have it in a curing tank... you also don't have to sacrifice damsels or other fish, there is a new addative called Bio-Spira, I did this and have had no ill effects yet.
Thanks Kelly - not only is there bio-spira but several other products that will introduce the beneficial bacteria too. Some work better than others with bio-spira getting a lot of good reviews.

Site References :

More Aquarium Setup Articles!
Freshwater Aquarium Setup
Freshwater Aquarium Setup
Learn how to setup a freshwater aquarium, from start to finish.
Reef Tank Setup
Reef Tank Setup
If you want to set up the ultimate aquarium, try your hand at setting up a reef tank!