Your tank is on cruise control and all SPS corals are in a happy zone, growing and thriving like you had always imagined. Then one day the lights come on and your eyes zero in on a dead coral. What the heck? How could that happen when everything was going so well?

Reef keeping can be a humbling experience, trying the patience of both beginners and veterans. Sometimes bad things happen due to poor husbandry and other times there is no clear explanation. I can sleep better at night when something bad happens as long as I know what caused the problem, allowing me to prevent it from reoccurring. That’s just the way I am wired. I like closure. It’s those mystery events that drive me batty.

Rapid Tissue Necrosis or RTN can be one of those mysterious events. RTN is when a SPS coral suddenly loses tissue and turns white. This bleaching event occurs within 24 hours and can effect the entire coral or just a part of it.ty MORE