Water Chemistry

Understanding Aquarium Water Chemistry.

example of aquarium


Water Chemistry is the single most important component of a successful aquarium. Without proper water chemistry, an aquarium will never be successful.

Water Parameters

Community African Cichlids Plants & Soft Water Fish Discus Brackish
Temperature 75° - 80° 74° - 80° 75° - 80° 82° - 86° 75° - 80°
pH 7.0 - 7.8 8.0 - 9.0 6.5 - 7.4 6.5 - 7.0 7.8 - 8.4
Ammonia 0.0 0.0 0.0 0.0 0.0
Nitrite 0.0 0.0 0.0 0.0 0.0
Nitrate <50 ppm <50 ppm <30 ppm <10 ppm <30 ppm

Cycling your new aquarium, which will establish or start the growth of nitrifying “beneficial” bacteria, will start when you add your first fish. The new aquarium cycling will take 4 or more weeks. The process depends on the water volume, the number of fish, the amount of food given, and the amount of space that the beneficial bacteria has to grow on. It will be best to start slow and allow the cycle to properly go through its cycle while trying to avoid the dreaded new tank syndrome, which will result in fish dying. Here is how the nitrogen cycle works. Let's say we are working on a ten gallon aquarium. You have added your substrate, plants/decor, treated water, added some seed bacteria to the aquarium, and your first four fish, guppies, in this example. You feed your fish some food. The guppies eat the food and then process the food and eliminate it. The waste turns into Ammonia, the beneficial bacteria then converts the Ammonia to Nitrite, then the Nitrite is then converted into Nitrate by the beneficial bacteria and then Nitrate is removed thru regular water changes.

As the days go by beneficial bacteria is reproducing, being able to process more and more. Once the water parameters have spiked, the parameters will start going down and your aquarium parameters will become more stable. Once the parameters have stabilized, you can slowly start adding more fish. It is best practice to slowly add new fish to the aquarium so as to not unbalance the water parameters.

There are several products you can add when setting up your new aquarium that will help with seeding your aquarium with beneficial bacteria.

When setting up your new aquarium, test your water before anything is added to the aquarium. Twenty four hours after you add your fish, test your water again, and do a 25% water change. In another 24 hours, test your water again and do another 25 % water change. Do this for your first week, then test your water every other day for the second week and do 25% water changes. After you see your water parameters spike, watch for your parameters to drop and then you can slowly add more fish. Never do more than a 40% water change on your aquarium at this stage as it will basically put you back to square one. Once your aquarium has become established, you can begin maintaining your aquarium with weekly water changes.

Water Conditioners

Creating the perfect living environment for fish will involve treating your water to make the conditions favorable for your fish to inhabit. There are many different companies and brands that make conditioners, some are better than others, but they all serve the same purpose, to treat your water and make the water parameters perfect for your fish. Water conditioners will eliminate chlorine, remove heavy metals, ammonia, nitrites and nitrates from your water. Some water conditioners also contain a slime coating that is important for protecting the fish.

Another water conditioner product to look for when starting your aquarium is a product that will jump start your beneficial bacteria. Several companies make this product but two of the best are Stability by Seachem and Seed by Aquavitro. Both of these products safely and rapidly establish the beneficial bacteria in the aquarium and the filter media.

pH is the measure of water acidiciness or basic of the water. 7.0 is considered neutral. Freshwater aquariums do best between 6.8 and 7.6, while some specific fish may prefer higher or lower, but most freshwater fish prefer the pH to be between 6.8 and 7.6.

Ammonia is a byproduct of fish waste. Ammonia is deadly to fish. A well established and maintained aquarium should have zero ammonia. If there is ammonia in the aquarium, it is best to figure out if feeding too much, too many fish or lack of beneficial bacteria. While trying to determine why ammonia levels are too high, do 25%-30% water changes daily until level is acceptable. IF the ammonia level is sky high, do at least a 60% percent water change, avoid feeding for 24 hours and try to vacuum the gravel to remove any detritus or debris from the substrate. Ammonia is a killer to fish and even as little as 2 ppm is deadly.

Nitrite converted from ammonia and high levels of nitrite inhibit the oxygen exchange in the fishes’ bloodstream and will cause them to suffocate. If you notice your fish swimming at the top of the water level gasping for air, your fish are likely suffering from nitrite poisoning and immediate action needs to be taken, just like with ammonia poisoning.

Nitrate is the conversion of the nitrite by the beneficial bacteria. While nitrate is not as harmful as nitrite, it is still harmful to fish and long term exposure can stunt growth and exposure to high levels for long periods of time can cause undue stress and compromise their immune systems. Live plants are excellent at keeping nitrate levels down.