Last night when I came home from work I noticed my Porc Puffer had a spot on his eye that looked pretty serious. :thinking: I took a picture of it and headed to the LFS for medication. After talking to a LFS "expert" he recommened a copper based medication for my puffer. He mentioned that if I treated the fish in my maintank I would never be able to keep inverts or corals due to the copper. No big deal, it's a FOWLR tank, I have no need for inverts or corals. So, I added the medication to my tank, my 220 gallon tank with 180lbs of live rock. I wake up this morning and my normaly clear tank is cloudy. Concerned, I throw a question out there on the forums concerning copper meds and find out that the copper will kill everything in my tank with the exception of the fish.Now in panic mode, I change 40 gallons of water, add carbon to the tank in an attempt to savemy LR. Within 2 hours my ammonia went from 0.5 to 5.0. Every pound of live rock that was in my tank had to come out and is now part of my new zen garden.I just spent $1000.00 re-ordering live rock, new substrate and salt mix. I also flooded my downstaris when I forgot the hose was running. My wife reminded me about it when she got home and saw water flowing through the garage. Lesson learned......copper in QT tanks only!