yea but you said water water was in check. With LPS they are very sensitive to alk swings... but then you can get an infection because there weak. Just like humans, not everyone gets sick but when your stressed your more susceptible to succumbing. Vit C is an antioxidant which perturbs oxidative stress LPS are sentive to oxidation due to the high cincentration of algae making it within there skeleton. Iodine helps deter this as well thats what the dips do. Iodine + O2 = Iodate. O2 is poison to lots of creatures in too high amounts. Once this stress takes its toll then infection could set in. I am not saying by any means this is whats going on for a fact, that would be impossible to say over a forum. but these things happen more often than one may think and like i said treatment is the same... dip and amputate