I need HELP please. I think in my tank, the biggest one, I over taxed the bio filter by adding two 6 inch oscars. I am about to lose one of my silver arow's. I saw him this morning the the color was already peeling off his top, by his spine, and the older one that is about 10-11 inches was racing all around the tank last night, was sitting calm on the top this morning, still have crickets and Rosie's in the tank. The Oscars are kinda doing the laying on thier side thing. The ammonia was approaching the warning levels, I think about a .03. I realize the Oscars got added too late, and have had suggestions to add on another filter for more surface area on bacteria. I am confused how this might help. My tank is a 75 gallon tank, and the filter is rated for 110 gallons. I am sure by the time I get home, that younger Arow is going to be dead. I am going to return the Oscars so they don't die, but what can I do to save the other one? Is there treatment for Ammonia poisoning?