Black smelly stuff inside tonga branch

[cbarria]

As I was cutting some branches from this "tonga branch" rock to separate the corals from it, I broke off one branch that had some black nasty stuff inside. It smelled pretty bad. It was inside the tonga branch rock. The rock itself looked very healthy and the corals too. What's this black stuff and how bad is it? Should I try to clean it out?

Thanks

 

[wildemon]

Black smelly stuff is certainly bad. Usually the odor is sulpher in a non-oxygen bacteria culture. A day late, but hopefully you decided to cut out the bad parts. The rock will probably be good to use after you quarantine in a separate tub with a skimmer. All live rock is vulnerable to the situation you describe and an extended session in a separate tub used to be normal before use inside the tank. Obviously the corals on the outside would be safe for your tank but if you had not broken it open, the rot inside might have polluted your display.
William Fisher