Evalive Aquarium in Frankston has the best and biggest range of fresh water fish available. We have the biggest range of African cichlids in Melbourne We serve Melbourne,Cranbourne and the Mornington Peninsula. Cichlids, Aquariums, heaters accessories plants tropical natives Nitrate is produced from nitrite by Nitrobacter bacteria
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Nitrate is produced from nitrite by Nitrobacter bacteria, and is an end product of the biological filtration process. Nitrate is not considered harmful to fresh water fish in concentrations under 50ppm. A recent study has shown that concentrations of nitrate as low as 20ppm, cause significant mortality in eggs and fry of Chinook salmon and rainbow trout. It therefore seems that tolerance levels of fry and adult fish to nitrate, may vary. Discus in particular seem to be quite sensitive to high nitrate levels.


Nitrate test kits are available, and prove to be a valuable water quality monitor.


Theoretically, nitrate should just keep accumulating in an aquarium, as ammonia and nitrite are oxidised. In practice, this does not happen. Some nitrate is converted to nitrogen gas and driven off. Aquatic plants and algae assimilate nitrate as plant food, and it is diluted with every partial water change. This is one good reason why shop tanks should have a 1/3 water change weekly. In home aquariums with more plants growing, and lower fish populations a 1/3 water change every month should be sufficient.

Aquarium de-nitraters are now available, these units work by allowing anaerobic bacteria to convert nitrate to nitrogen gas, (like conventional biological filtration in reverse).