Starting a fish tank

The first six weeks after you set up a tank, this is what happens.  The dreaded ammonia cycle.  This happens in the first six weeks, once you add the first fish to the tank and start the biological cycle happening.

Bacteria that eat waste need to build up in your tank to protect your fish from the effects of those waste products.  The problem that occurs is during that build up, if you feed too much or put too many fish in the tank, you can cause these peaks to go too high, and reach toxic levels.   It is like an aquatic septic field, it takes some time to be able to handle a full load.

The best way to cycle a tank is to do what we like to call a “soft cycle”.  This means introducing only a few fish (no more than 25% of the total capacity of the tank), and feeding less frequently than you normally would (once every two days should be fine, what they can eat in a few minutes only).  If there is any left over after a few minutes, reduce the next feedings size.

During the first six weeks, the tank will be much more susceptible to accidental overfeeding, or to the effects of a dead fish polluting the tank.  It is very important that you monitor your tank to make sure these do not happen.

“Hard cycling” a tank is faster, but you do not stock with any fish, and need to dose with ammonia, urine or other waste producing matter and monitor the tank closely with expensive test kits until it tests clear of nitrite.  Faster, but a lot more work and expense, and best left to experienced aquarists.

Some people suggest cycling with feeder fish.  Unfortunately, feeder fish are not the healthiest of fish, and can contaminate your tank right from the start.  And then, after the tank is cycled, what do you do with them?

The easiest method is the soft cycle, put in a few fish, use Cycle bacteria booster, and let nature do its job.  Nothing good happens fast, patience is the key.  Start with a few of the hardiest fish you want to end up with, and its easy.  Just take the six weeks the tank requires to mature, and you shouldn’t have any issues.

 Water Change

More than any other factor, water change is the most important thing in maintaining an aquarium’s water quality, and thereby, the fish’s health.

Many people believe that topping up evaporated water is water change. This is one of the most dangerous mistakes that is made in keeping fish. Evaporated water is pure water. That is how distilled water is made, by evaporating (boiling) water and collecting the steam. This process leaves all impurities and minerals behind.

Similarly, in a fish tank, evaporated water leaves behind the minerals and impurities. Then you add more tap water, concentrating those impurities. This makes the water get harder and harder as the minerals build up in the water.

The other benefit to proper water change is the removal of waste products that build up in the tank. Each time you feed the fish, after the fish use the nutrients, they expel waste, which stays in the tank. You may not see it, as the bacteria in the tank break it down, but it is there. These waste products can also change the water chemistry as well, causing the water to become increasingly acid over time.

So, if proper water changes are not done, the tank water, which may look fine and clear, gets progressively harder and more acid. Your fish get used to this gradual change, and can look healthy until they hit the crashing point. And that point can come with the introduction of a new fish. The new fish, not used to the hard acid water your fish have gradually become used to, goes into shock, is stressed, and can break out in a disease, like Ich. And then the rest of the fish, who are stressed but look healthy, come down with it as well, and you have a whole tank wipe out, which is usually blamed on the new fish, but it is actually the improper water changes and bad water that caused the problem.

Changing water doesn’t need to be difficult. 10 to 20% per week is usually more than enough, and isn’t enough to stress the fish. More than 20% at a time can be stressful on the fish, so smaller, more frequent changes are recommended (and easier for you).

When changing the water, use a “gravel vacuum” to remove the solid waste building up in your gravel. But don’t try to do the whole bottom all at once. Break it up into sections, doing about 1/4 or 1/8th of the bottom each week. That way, you can do a better job on the section, and the whole bottom gets cleaned each month. You can use tap water that has been treated with Aqua+, and is around the same temperature as the tank.

Proper water changes will help your fish stay healthy, your tank look clean and your aquarium ownership a rewarding hobby.

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