I use it to and my corals love it. My shrooms are spreading like a germ. When I smelled mine it smelled rotten too like dead fish or something. this is the second bottle I have gone through and they both have smelled that way. whatever the smell is my corals really like it, so i am going to use it for a long time. also I keep mine as cold as I can without freezing it. for some reason when it is cold like 34,33,32 deg's it seems to work better. I had it at a warmer temp when i first started usin it and my corals didn't respond as well as they do when it is on the verdge of freezing. IMO