Tropical Fish Keeping
The most important thing to remember in setting up and maintaining aquarium is this:
"We don't take care of fish... we take care of water. Take care of the water, and the water will take care of the fish."
It's very true - you won't be taking your fish' temperature, or taking them in for x-rays - you will be testing the pH, ammonia, nitrate and nitrates in the water and you'll be checking the temperature - of the water... not the fish! An established, properly stocked, well-maintained aquarium rarely has any sick fish. They live and breathe that water day in and day out, so it's important that you keep it as clean and healthy for them as possible. For species specific information on aquarium setup, try asking over at http://www.tropicalfishtalk.com
Part 1: The Cycle
No, don't get excited, fish cannot ride bikes ( yet - still working on it! ) The cycle refers to the nitrogen cycle that occurs naturally to clean the water. Fish waste and uneaten food turn into ammonia - which is highly toxic to fish. If the ammonia level gets too high, they will struggle to breathe, their gills and eyes will burn, and they will eventually die. Ammonia in the tank is a very serious problem - fortunately, the cycle takes care of that for us. Beneficial Nitrosomonas bacteria eat the ammonia, and convert it into nitrite. Unfortunately, nitrite is still toxic to fish, but not quite as much as ammonia, so at least we're getting somewhere! Another type of beneficial bacteria called Nitrobacter bacteria converts the nitrite into nitrate, which is far less toxic than nitrite. While any presence of ammonia in the tank can hurt the fish, all but the most sensitive fish can handle a few ppm (parts per million) of nitrite for short periods of time. Most fish can handle up to 40 ppm of nitrate on a fairly regular basis, and up to 60 or even 80 ppm for very short periods of time. So, the cycle takes a horribly toxic chemical (ammonia) and converts it to a less toxic chemical (nitrite), and then into a much less toxic chemical (nitrate).
Unfortunately, there are no bacteria that get rid of the nitrate, so that must be dealt with in a different manner in order to keep the levels below 40 ppm. Live plants utilize nitrates as a natural fertilizer, but special equipment and a lot of know-how is needed to maintain a successful planted aquarium. The easiest solution, is regular water changes - which you need to do anyways. If you have 40ppm of nitrate in your aquarium, and you do a 50% water change using water with 0 nitrates, then you effectively dropped your nitrate level down to 20ppm. If your nitrate levels are really high (anything over 40ppm), you should do a bigger or more water changes.
Two Water Change Methods To Quickly Drop Nitrates (or nitrites or ammonia!) in the Aquarium
For either of these methods, pay special attention to the temperature and pH of the water. When changing out this much water, you need to make sure they are as close as possible to the water currently in the tank.
- 75% Water Change
By increasing the volume of water changed, we can drop the levels much quicker. If your nitrate was at 60ppm, and you do a 75% water change, that will drop your nitrate level down to 15ppm - a much safer level.
- Double Water Change
For this method, you simply do 2 (or even more) water changes, back to back. If your nitrate level was up at 60ppm, the first 50% water change would cut that back to 30ppm. A second 50% water change would cut that back to 15ppm - the same as doing a single 75% water change.
Those are the basics on the infamous cycle. Be sure to check back soon for Part 2: Choosing an Aquarium