So I've got about 7-8 years freshwater experience under my belt and are about to dive into marine aquariums now. Just writing a document for my use of the chemistry of marine so I understand it all. Firstly I'm looking at Ammonia, like any tank I understand Ammonia comes from fish waste and uneaten food etc. Does anything else in Marine tank cause Ammonia? (Coral?). Other than water changes, removing excess for etc how else can you remove Ammonia from your tank and ensure it's converted into Nitrites?