Straight to the point....Will ParaGuard destroy all the biological filtration of live rock and sand? I know that it isn't 100% invert safe. I have a Huma Trigger that started displaying cloudy fins this morning. I highly doubt I will be able to catch him. He is in a 90g tank, but only about an inch long. I am thinking my only solution would be to drain the tank as low as possible to try to catch him. I will upload a picture of the fins tonight when I get home from work. Not sure what it is, but I don't think it is ick. I have had SW fish for 15 years and never had a sick fish.