Brown jelly infection are common in LPS
corals where the water paramaters are less than par. Elevated nitrate being a major source of the problem. If the coral becomes damaged in any way, even if casual (crab/fish/shrimp et al), it can lead to these problems.
Brown jelly should not set in so readily unless the water quality is off some. Are you 100% sure all nitrogens (NH3
) read zero? Do you know your alk
What fish inverts are in the tank, do you use a skimmer, how often are water changes performed, do you use carbon and how old is the tank?