Seachem Prime is a concentrated water conditioner for freshwater and saltwater aquariums. One dose neutralises chlorine and chloramine from tap water, making it safe for fish, invertebrates, and axolotls. The 500ml bottle treats up to 20,000 litres, so it suits everything from a small tropical tank to a heavily stocked display.

Prime does more than dechlorinate. It detoxifies ammonia, nitrite, and nitrate into forms your biological filter can still process, which helps stabilise a new tank during cycling or buy time if levels spike in an established one. It also binds normal concentrations of heavy metals found in typical tap water. The concentrated formula means dosing is small — a little goes a long way.

Aquarium keepers reach for Prime because it covers the essentials in a single bottle: safe tap water, ammonia and nitrite protection, and heavy metal binding. It's the default conditioner in most Australian fish rooms for a reason — it works across freshwater, marine, and axolotl setups without a fuss.