Just to figure out what happened. I recently noticed some white scratches on my male clown fish which resembled symptoms of brook. They were both healthy looking, swimming and eating well. I have never noticed them flashing either. So I figured that I should just go ahead and give them a 30 minute formalin bath at 2ml. I didn't notice any cuts or open wounds on them either. After I took them out I freshwater dipped for 1 minute and then into a clean tank. They seemed to be gasping and barly holding themselves upright. I feared for the worse and this morning the male clown passed. The female clown is still looking pretty bad and I fear she won't make it much longer. I'm not sure what happened, did I misinterpret the white marks as maybe something else? I should add that these clowns were less than an inch.