How long do I have to leave the water in my fish tank before adding the fish?

Question

I have got a fish tank rady for a few tropical fish but im unsure how long to leave the water before its ready to put my fish in

Answer 1

Having a successful tank is not difficult, nor is it necessarily a lot of work, provided you use some common sense. These guidelines are based partly on science and partly on experience gleaned from aquarists having many years experience in ``the art of fishkeeping.'' The following list summarizes the most important rules for success. Each is discussed in more detail in subsequent sections of this document.
Have patience.
Buying a tank, setting it up and filling it with fish all in the same day, while possible, is a sure road to disaster. In fact, setting up and fully stocking your first tank will take close to two months!
An ounce of prevention is worth a pound of cure.
Providing an environment that minimizes fish stress is the key to success. As fish become stressed, their immune systems weaken and they become more susceptible to disease. Moreover, most fish medicines don't work very well, aren't worth the money, and frequently do more damage than good. Often, the best treatment for sick fish is to relieve stress by
performing regular partial water changes,
not overfeeding,
checking that your filtration system works,
giving them enough room to live, and
keeping them with compatible tank mates.
(See the STRESS SECTION of this FAQ for full details.)
Understand and respect the nitrogen cycle.
Fish produce toxic wastes (ammonia) that must be broken down by bacteria through biological filtration. Most fish deaths for first-time tank owners are a direct result of not understanding the nitrogen cycle and are completely avoidable. (The NITROGEN CYCLE SECTION explains how the process works.)
Perform regular maintenance on your filter to keep it clean.
Dirty (clogged) filters operate at reduced efficiency. In the case of biological filtration, a clogged filter will be unable to remove ammonia properly, resulting in fish stress and eventually death. Floss-based biological filters are cleaned by gently rinsing them in used tank water that has been siphoned into a bucket. Undergravel filters are cleaned through regular vacuuming. (Filters are discussed briefly in this beginner FAQ, and in more detail in their own FILTRATION FAQ.)
Properly treat all tap water before adding it to your tank.
Municipal water contains such added chemicals as chlorine or chloramine to make it safe for human consumption. These substances are toxic to fish and can weaken, damage or even kill fish. (See the WATER TREATMENT section of this FAQ for details.)
Take the time to learn basic water chemistry
Basic water chemistry is pH, hardness and buffering. You needn't enroll in a chemistry course, but you should know enough about water chemistry and the specifics of your local water supply so that you can keep fish happy. Every location's water source is different, and some fish won't be able to survive in your water. You can learn details about your water from a local fish store, through the use of test kits, and from local aquarium clubs (or, amazingly, from the CHEMISTRY section of this FAQ).
Keep the pH of your tank's water stable.
Rapid pH changes stress fish. Tank water has a natural tendency to become acidic due to the production of nitric acid (nitrates) from the nitrogen cycle. Keeping pH stable requires having adequate ``buffering''. If your water is soft, you may need to add buffering agents. Again, see the CHEMISTRY section for details.
Avoid adding chemicals that lower the pH (e.g. ``pH-Down'').
Such chemicals frequently have undesirable side-effects (e.g., stimulate algae growth). Moreover, in most cases (despite what books and stores tell you) the pH of water DOES NOT need to be adjusted to make it ``more perfect'' for a particular species of fish. If the pH of your tap water is between 6.5 and 7.5, it is just fine for most fish. (This is discussed in the CHEMISTRY section too!)
Pick fish for your water.
Select fish who are native to waters having a similar chemical properties (pH and GH) to your local tap water. If you have hard water, choose hard water fish. If you have soft water, choose soft water fish. This is especially important if you water is outside the 6.5-7.5 pH range. Changing the natural hardness (or pH) of your tap water can be hard work and often takes the fun out of keeping aquariums. Moreover, bungled attempts at adjustment are common and often worse for fish than the original sub-optimal water conditions. A good way to learn which fish live happily in your local water is to check with a local fish store (or club).
Choose the fish to fit your tank.
Select fish that are compatible with each other and think long-term. That 1 inch fish sure looks cute at a store. But what will you do when it gets 6 inches long and views its cohabitants as potential meals? Fish have specific minimal space requirements that are dependent on their physical size and temperament. Select fish whose needs will be met in your tank. Be sure your tank has adequate hiding places (e.g., rocks, plants, driftwood, etc.) for its inhabitants.
Properly acclimate fish before adding them them to your tank.
(Details are covered in the section on ADDING FISH.) NEVER add store water to your tank (it may contain diseases), and if feasible, quarantine new purchases for 2-3 weeks before adding them to your tank.
Perform regular partial water changes.
Changing 25% of your tank's water every other week serves two purposes: it dilutes and removes nitrate before it accumulates to dangerous levels, and it replaces trace elements and buffers that get used up by bacteria, plants, etc. Finally, regular partial water changes help insure that your tank's water chemistry doesn't deviate significantly from that of your tap water. The latter benefit is especially important should disease strike your tank; water changes are the most important step in controlling disease, and large water changes are not safe unless the chemical composition (e.g., pH and GH) of your tank's water is similar to your tap water.
Shop only at ``reputable'' stores.
Sadly, many pet stores are more interested in taking your money than selling you healthy fish. It is almost always worth spending a little more money to get quality fish. Diseases introduced to your tank with newly purchase fish may infect your other fish with catastrophic results. Buying a low cost fish is also not much of a bargain if it dies less than a month later. But many stores will instead try to sell you equipment and medications you don't really need. Your best defense is to arm yourself with knowledge so that you can properly evaluate their advice. Some hints for finding ``reputable'' stores can be found in the STORES SECTION.
The above summary serves as a reminder of the principles that lead to happy fish keeping. Each of these topics (and many more) is discussed in the remainder of this document.

How much time and effort is involved in keeping a fish tank?
For a 10-20g tank, once it is set up, expect to spend about 30 minutes every other week doing partial water changes, cleaning the tank, etc. If this is too much time for you, DON'T GET INTO THIS HOBBY! You will also spend a few minutes once or twice a day feeding your fish, turning the lights on and off, etc. Warning: many people spend much more time than this simply looking at their tank and its inhabitants. Of course, that is the whole point. :-)
Be prepared to spend several hours researching the hobby before you make your first purchase. The more time you spend BEFORE you actually get the tank, the smoother things will go. Go to several pet stores to find one that looks like a reputable place. Visit them again several more times. Get some beginner books. Read this beginner FAQ several times.

Most people who get frustrated with fish tanks made mistakes that could have been easily avoided. The way to avoid mistakes is to learn the basics (e.g., the nitrogen cycle) BEFORE you put fish in your tank. There are few things more upsetting than frantically reading the FAQ for the first time, while three feet away your beloved fish are dying. Remember: most aquarium problems are easy to prevent, but hard to deal with after the fact.

Answer 2

I think you need it to run for at least a week, and maybe two. If you want to put fish in sooner, you might try adding some water from an existing tank, as long as there are not diseased fish in the tank. There has been mention made that you can't keep sharks in a small tank. Do you mean sharks like the Red-tailed Shark, which is actually a type of bottom feeder, or do you mean a real shark? Try keeping true tropicals in a small tank. They are fun to keep and the right size. You can keep a Ghost Fish, Eels, Flounder, or Knife fish if you want something more exotic. Silver Dollar fish are also fun to keep and are considered community fish. The others may not be suited for the community tank, other than the small Flounder, which is not too noticable in the tank. Angel Fish are also enjoyable and interesting fish to keep.

Answer 3

Hi, it is recommended you have a thermometer on the side of the tank so you can see what temp the water is, i know if may take a few days up to a week, it takes 24 hours for cold water to reach room temp, but it is completely different for tropical fish. But dont put the fish in till you get a thermometer and check the water as all you fish could die and it would be a waste of money

Answer 4

A couple of weeks at least. If you have a friend with an established fish tank and healthy fish, ask to borrow a quart or gallon to start your tank. Let your new water sit overnight or treatmt it with chlorine remover so it does not kill the good bugs in your friend's water. The beneficial bacteria or "bugs" in mature water are what make the environment good for the little fishies. Seeding a new tank with some mature water will speed up the process. You can also buy some canned "bugs" at the fish store. Have fun. I have missed having a tank and plan to set one up ASAP.

Answer 5

If you are using tap water, it may contain chloramine in addition to chlorine. Chlorine is unstable and will evaporate if you let the water sit. Chloramine will not go away just by aging the water (i.e., letting it sit). You need to add a tap water conditioner such as Amquel or Stress Coat to make the water safe for the fish. Also, please note that a new tank is unable to handle a "full load" of fish, so start with only one or two hardy fish to "cycle" the tank -- that is, for a colony of beneficial bacteria to grow. The bacteria will convert harmful ammonia into less harmful nitrites, and then another type of bacteria will convert the nitrites to the relatively harmless nitrates, which are still harmful to the fish. Get a water testing kit and test for ammonia and nitrites daily until both read 0 ppm. Then you are ready to put a full load of fish in the tank, or one inch of fish per gallon of water.
You can speed up the process by buying a product called "bio-spira" which "cycles" the tank virtually overnight.
You can also cycle the tank without fish by using household ammonia (pure ammonia).
Please do read the following article to avoid the "new tank syndrome."
http://freshaquarium.about.com/b/a/238045.htm

Answer 6

if your in the uk a week never put fish into a tank on weekends as they double dose the water with chemicals or you can buy a water treatment from any good pet shop then you can add fish in a couple of hours i think its called aqua-safe.also make sure you float the bag with fish in to get the temperature of the water the same as in the tank about a hour will do as the shock of the different water temps will kill the fish also

Answer 7

Ideally fish should only be added to a fully cycled tank. Otherwise ammonia and nitrite poisoning can occur within the first 6 weeks of set up (usually resulting in some losses).

If you have a filter with established bio-media, you can add fish immediately (be sure to dechlorinate the water first).

Answer 8

Until the water is crystal clear. the water first turn "cloudy" after three or four days. You need to be patient, but the waiting worths. Obviously, you need to set the tank first, wait the necessary time, and JUST THEN, select your fishes. Leave them in the bag they come from the store for about three hours, putting the bag touching the tank water, then release them into the tank.

Answer 9

The tank will get cloudy as your algae bloom then it will suddenly go crystal clear. Likely to be 2 to 3 weeks. That means your tank has matured and ready for fish. Some fish are very sensitive to unmatured tank an dthe shock will likely kill them so be careful.

Answer 10

depends on the fish cold water or tropical if it is cold water 2-3 days tropical about a week for the temperature to steady out

Answer 11

I think you should wiat for 2 or 3 weeks to add fish to your tank that way it gives the tank time to filter through the water to make sure it ready to go. I also think you should use spring water at room temp. to set up your tank it work for me.