Is aquarium water testing really necassary? - In a word - YES! In newly set up aquarium, water testing is critical to avoid fish loss as ammonia and nitrites rapidly rise. In an established tank, water testing is important to ensure the continued health of your fish. Water testing kits should be considered part of the operating expense associated with keeping an aquarium! Find kits from JBL, N.T Labs, Dymax, Ista, Red Sea, Salifert, Seachem and TMC.