Basic Guide to a Freshwater Aquarium

By Pat Bridges
Pat edited "The Scat" - newsletter of the St. Catharines Aquarium Society, Canada, for 9 years

Read these notes and maintain a healthy, problem-free aquarium. You won't encounter the usual problems that occur and you won't be among those who ask "Why did my fish die?"

Assuming you have acquired a fish tank that doesn't leak and have installed an adequate form of aquarium filtration, a heater (necessary for most tropical fish), a cover (preferably containing a source of light) and have added water, your tank is now starting the process of becoming 'balanced'. This will happen and takes several weeks, at the end of which the 'good bacteria', necessary to support life in your aquarium will reign supreme! This process can be speeded up by immediately adding a) half a dozen small fish (see below) that will produce waste to feed the bacteria, and feeding the fish lightly once or twice a day b) some water from an already set up, healthy aquarium, which already contains good bacteria c) some gravel from an already set up, healthy aquarium, which already contains good bacteria or d) adding an amount of a product specifically designed for this purpose, sold at your local aquarium store. If you want to know more about this 'cycle' of the aquarium there are many books available on starting a new aquarium that will explain it in detail. For now, suffice it to say that this cycle will happen and unless care is taken, disaster occurs. Your aquarium may develop a new tank bloom (fogginess in the water) while this cycle is occuring. It will clear.

During this time and as always, regular care and maintenance is IMPERATIVE if you want your fish to live long and healthy lives.

Make sure all equipment used for your aquarium is used only for your aquarium.

Fish may be put into your aquarium as soon as the water clears from setting up the aquarium and you are sure that all the equipment is working properly. As stated above, the fish will start that 'good bacteria' in the aquarium that is vital. Too many fish in your aquarium now, may result in losses. More fish may be added in a few weeks. Under NO CIRCUMSTANCES should you add any more fish until then and even then, add them a couple (if small schooling fish, add four or five) at a time over a period of a month or so. Try to choose hardy, easily maintained fish to start with. Some good choices are Danios, (they like to swim in schools), Platies and/or Swordtails, (lots of brilliant colours are available) and two or three Cory Cats to patrol the bottom. If you are obtaining your fish from someone who is knowledgeable and reputable tell them about your setup, including the size of your tank, and ask for their advice.

Change approximately one-quarter of the water in the tank weekly, making sure that the dirt in the bottom of the aquarium is disturbed and sucked out with your syphon. The replacement water must be very close in temperature to the water that you removed and ABSOLUTELY MUST BE DECHLORINATED WATER. THIS WILL AVOID ANY POSSIBILITY OF GILL DAMAGE. Also, if you buy the dechlorinating solution, it usually has other 'stuff' in it to reduce stress and maintain the slime coat.

Continue regular maintenance, once a week. It should take no more than 15 minutes.

Keep an eye on the temperature from time to time. A drop in temperature will encourage stress-related diseases, e.g.: 'Ich' and enough of a rise in temperature would cook the fish and the good bacteria, resulting in the loss of your efforts.

When changing water, the best advice is to unplug your heater and power filter. Failure to unplug your heater and possibly exposing it to the air could result in cracking of the heater glass. The important thing here, is to remember to plug everything back in after!

Keep the glass clean, both inside and out. This can be done with a razor blade type of scraper, or bunched up white paper towels. Keeping the glass clean is necessary for aesthetic reasons, obviously, but also so that you can quickly notice any changes in the behavior of your fish that will alert you to the fact that something might be amiss.

If you are using a power or box filter, ALWAYS leave half of the dirty filter floss (if that's what you are using) in the filter, leaving some of those 'good bacteria' to continue their valuable work. (Change your filter floss when it is really dirty and/or the flow rate from the filter has slowed down noticeably). Rinse out the sponge in the power filter, if you are using one, under TEPID water - never hot. Using hot water will completely destroy the good bacteria that you are striving to establish and maintain. Charcoal, if used, can be rinsed each week--tepid water again. Replace at least once a month. In between times, when it looks really dirty, it is o.k. to rinse it under the tap - TEPID water again.

AFTER THE INITIAL PHASE IS OVER, maintain a regular schedule as always, keeping in mind a few important things that will ensure a healthy aquarium:

  1. It is inadvisable to add store-bought fish to your aquarium unless you can quarantine* them for at least three weeks. Some people may laugh at this because they've never had a problem. However, it takes one unhealthy fish to wipe out your entire population and it does happen. Unless you are ABSOLUTELY sure of your source, PLAY IT SAFE. If you do have a quarantine tank, maintain the same schedule of care as your main tank so that when the time comes to put your fish into the main tank, the water will match and there won't be any shock involved (either to you or the fish)!
  2. When you quarantine, it is essential that you wash ALL aquarium equipment under hot water after any use. Otherwise you run the risk of transferring disease. NEVER USE HOUSEHOLD SOAP when washing aquariums and related equipment. Salt can be used as an abrasive/cleaner or a very dilute bleach solution can be used when cleaning equipment. Always rinse well afterward.
  3. When obtaining fish from ANY SOURCE, never put the water that they came in into your tank. Pour the fish and water into a net and put only the fish into your aquarium.
  4. When bringing new, healthy fish to your aquarium, check to see if the temperature in the container and the tank is close. A degree or so fluctuation is not harmful. You may opt to float your container of fish in the tank for a few minutes for the temperatures to equalize.

If you use plastic plants, wash them when dirt and/or algae are visible. Live plants can be added shortly after your initial aquarium 'cycle' has finished but once again, unless you are sure of your source, you might be adding disease, snails or other unwelcome guests, unless precautions are taken. If you either don't care, or can't be bothered, plastic plants are for you. If you do care, a brief live plant sterilization*** can be used although this doesn't always get rid of snail eggs. So, sometimes, even though you are careful with new additions, snails may appear in your aquarium. Then the best you can do is to take them out as you see them.

If you have live plants in your aquarium, they won't survive unless they have enough light. This usually means at least 10 hours per day. A timer is invaluable for this. (A timer is only usable on lights that are 'quick start' or incandescent). They are inexpensive and a must if you ever spend a day or two, or more, away from home. Be sure to plug only your lights into the timer. The heater must be on all the time during the cooler weather and the filtration must be non-stop all the time. If you have only plastic plants, then the length of the aquarium 'day' will be up to you. Try to keep the 'day' uninterrupted if possible. If the aquarium is in an otherwise dark room, the on and off of lights is stressful for the fish. Keep in mind that incandescent lights produce more heat than fluorescent lights. During hotter weather, this might be a problem.

Keeping the temperature between 75 and 78F should work well for most tropical fish.

So - minimal care of the right kind can keep your aquarium in top shape. Your aquarium should be good for many years of uninterrupted enjoyment.

Anytime you are away from home for a day or more: don't overfeed your fish just before you leave. Food they can't eat will rot, grow fungus and smell. Your adult fish will be o.k. for a weekend, even a week, without feeding. If you are going to be away longer and someone else feeds your fish, TELL THEM TO FEED ONCE EVERY OTHER DAY, while you are away and ONLY SMALL FEEDINGS****. SHOW THEM HOW SMALL! More tanks have gone bad due to overfeeding by well-meaning fish-sitters! Your fish will survive longer unfed, while you are away, than they will if they are overfed.

Tank Smell
Your aquarium will never smell - unless you have overfed or a fish has died. Eyeball your aquarium for dead fish or other problems, once a day - before lights out is a good time.

Sometimes, due to a number of circumstances, algae will become a nuisance. Regular maintenance will get it off the plastic plants and interior of the glass, but if its growth becomes rapid and unsightly between weekly cleanings, too much light might be the problem, so reduce the duration of your light period slightly. Keep in mind that if your aquarium is near a window, algae will grow more rapidly even if there is decorative paper on the back of the tank. Plants are attractive and if algae continues to be a problem, adding more live plants might also help.

Quite often no matter how many helpful hints are listed, there are more questions, so don't forget, call a more experienced aquarist if you need help!

Winter is a time when some real emergencies can happen due to power outages. This doesn't happen often, but if it does, the aquarium will be fine for a couple of hours, as long as it isn't overpopulated. If it's any longer and if the temperature starts to drop, do a small (dechlorinated) water change using slightly warmer water for as long as warm water is available. This will be necessary every two or three hours thereafter while the power is off. Wrapping the tank with a blanket or taping styrofoam pieces on all four sides could be done to reduce heat loss for an extended period of time, but the water would still have to be changed every few hours due to lack of filtration and oxygen.

When the power is back on, uncover the tank and check to see that everything is working and the fish are o.k.

TO CALCULATE THE SIZE OF YOUR AQUARIUM (in U.S. gallons): Width x height x depth (inches) / 231 = gallons. (For example 12 in. X 12 in. X 24 in. = 3456 cubic inches. 3456/231 = 14.96 (15 gallons)

TO CALCULATE APPROX. HOW MANY INCHES OF FISH YOUR AQUARIUM CAN SAFELY HOUSE: Width x length divided by 30 equals inches of fish. (For example 12 in. X 24 in. = 288 square inches (of water surface). 288/30 = 9.6 (inches of fish) This is a very rough guide. You could have considerably more than this if the fish are tiny, such as Neon tetras but perhaps less if the fish is large and full bodied such as an Oscar.

TO CONVERT degrees Fahrenheit to degrees Celsius: Subtract 32 from the number of degrees F. and divide the result by 1.8. (For example 80 degrees F is 80 - 32 = 48. 48 / 1.8 = 26.7 degrees C )

Patience is important when you start up an aquarium. It always pays off.

* Quarantining: Use a small heated and filtered tank, with a lid. (Use a **'dirty' filter.) Take some of the floss from a filter that is in use, put it with some fresh floss in the filter in the quarantine tank. At least this will guarantee that your fish won't suffer as much stress from the tank going through the 'cycle'. The dirty floss already has some of those precious 'good bacteria' in it.

*** Sterilization of live plants: Use a tablespoon of Alum (available in any drug store) dissolved in a gallon of tepid, dechlorinated water, for five minutes ONLY! Remove from the alum solution and rinse in some clean, tepid, dechlorinated water. (Repeat this treatment several times at intervals over 7 to 10 days and then inspect the plants carefully. If no live snails, even very tiny ones, are found, it should be safe to place the plants in your tank.)

**** Feeding: Put A SMALL PINCH OF FOOD IN AND MAKE SURE THE FISH EAT IT ALMOST IMMEDIATELY. AFTER ABOUT 5 MINUTES, THE UNEATEN FOOD WILL SINK TO THE BOTTOM OF THE TANK AND MAY NOT BE EATEN. It will fungus, smell and look unsightly. Feed your fish once a day. Remember, most fish will always appear to be hungry. Variety in your fish's diet is a good thing.





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