Is to regularly deworm (I know correct terminology is to say worm them but that sounds dumb) them with CZ Aqua Clear. Fish can get internal parasites from stress alone and this stuff WORKS. Get it online from all4fish. Com free shipping or wherever. Your fish will thank you! Just sharing from experience I ordered flowerhorn from Thailand came with white poop and this stuff did the trick. The metro and prazi and api cure was such a waste...