I had a 75 gallon reef that I upgraded to a 90 gallon cube when we moved in May of 2014. I have 2 frogspawn colonies, one is the size of a basketball, the other the size of a baseball (the smaller is a frag of the bigger colony).
In October my basketball sized, perfectly healthy frogspawn started getting brown jelly disease, or rapid tissue loss. As the single heads were dying, the whole colony shriveled up and looked horrible. I would scrub the infected heads and suck up the tissue as to try not to allow healthy tissue touch the dying tissue. I performed daily water changes which slowed the spread but didn't completely stop it. After losing 6 heads in 2 distinct locations on the colony I read somewhere that it could be due to fungal infections. I dosed Chemi-clean on my tank per the instructions. I lost 1 more head during the Chemi-clean treatment but I had started to lose it prior to dosing.
I performed another massive water change after using the Chemi-clean and the tissue loss stopped and the colony started to bounce back. I'm not sure what caused the issue as all my water parameters had been perfect. I went to the LFS 3 times throughout the process and each time they tested my water and agreed that all of the parameters were fine. Throughout the whole ordeal, the smaller colony looked healthier than ever and never showed signs of being affected. I have had this frogspawn for about 5 years now and have never had an issue prior to this event.
The coral is fuller and bigger than ever now but I still get sick to my stomach thinking how fortunate I was and that it could happen again.