Ammonia, nitrites, and nitrates are all toxic to fish and must be quickly and effectively removed from the aquarium. A proper functioning biological filter will do this, and help establish a happy, healthy… 

Fundamental water parameters that influence water quality, such as pH, ammonia, nitrite, and nitrate, are relatively easy to monitor through routine testing. This article discusses common aquarium problems… 

There are three types of filtration for use in aquariums, chemical, mechanical, and biological. Of these three, mechanical and biological are a must for every aquarium. 

How to properly reduce nitrates and replace trace elements for healthier fish and live plants.