As a normal process, the fish tank needs to have its water changed at some point but bear in mind that the water composition should remain at an acceptable level where it can be 50% of the old water and 50% of the new water to be added to the fish tank. This is essential to make sure that the fishes do not get shock in the process and get killed. The water clarity does not always indicate that the water is healthy, or otherwise, it can however indicate that the water inside has just been cleaned but it still needs to be tested for nitrate, nitrite, ammonia and the like to make sure it is safe. In order to keep the hygiene and safety altogether, here are the important water composition guidelines below:
Normal pH range: 6.5 to 7.2
This is the acid/base (alkalinity) activity in the water
Rapid changes in pH levels are unhealthy for your fish or shrimps
Normal results: 0.0 mg/L
Chlorine and chloramine are found in city water and must be removed for fish.
The chlorine in tap water is toxic to fish. Use a dechlorinator such as Seachem Prime to dechlorinate any water before adding it to the aquarium.
Normal results: 0 ppm
Once an aquarium has been cycled, it should have no ammonia.
In new aquariums ammonia will initially be high due to the waste of fish or other tank inhabitants. These could be neutralised by Seachem Stability.
Normal results: 0ppm
Nitrite reduces the oxygen in your fish’s blood. Nitrite is the second by product from Nitrifying bacteria in your aquarium. Where it is located in the high oxygen concentration of your tank. Nitrite is very quickly converted into Nitrate when there is an anoxic environment that exists.
Normal range: 0 to 30ppm
Nitrate is produced in Anoxic environments where bacteria converts Nitrite to Nitrates. Nitrates are a slow killer to fish and shrimps. Nitrates is essentially a fertiliser and it encourages algae growth, to keep the nitrate levels low a water change is required.
Normal range: 4-12dGH
Hardness refers to the levels of calcium and magnesium in the water. Test the hardness of your tap water and make changes to the aquarium water as needed.
Normal range: 23 to 28°C
Sudden swings in temperature can harm fish. Use an aquarium heater to keep a consistent temperature.
Total Dissolved Solids
Total Dissolved Solids although not critical in an Fish Environment is critical in a Shrimp or Guppy Tank.
A normal range for Neocaridina Shrimps are under 300ppm
A normal range for Caridina Shrimps are between 120-180ppm
A normal range for Guppies are between 300-500ppm