Haven't read through all the pages... too many to go through... but there was reference to if anyone had adverse affects to post as well. Algaefix does work. I tried it on my 15g frag tank and saw how well it was working and decided to try it in my 35g SPS. I had a odd bubble algae that came in on rock from an LFS that was impossible to get rid of and it started dieing with the Algaefix treatment. However, it also affected all my Acros. With 4 tanks it pretty well narrowed it down to the Algaefix since I only dosed those two tanks. I incurred losses... however I saw what was happening and was able to get a few frags of each coral, but I lost the main colonies. The montiporas were fine, all LPS were fine, pavona, porites and turbinaria unaffected. I lost both cleaner shrimp and one peppermint shrimp and my favorite emerald crab. I moved all the acro frags to my 60g soft coral tank and the've recovered well with only 2 more losses. Right after the treatment I incurred a really bad case of red cyano in the 35g which is just now going away (been about 2-3 weeks I guess). The bubble algae that tries to come back ends up dieing so the Algaefix must still be having an affect. The 15g frag tank is empty except for a Royal gramma and 2 peppermints and one small porites frag. No cyano but seems like some dinoflagellate are starting to creep up.