I came across this (very) old review written for reef tank owners about toxins produced by hard corals. The title really dates it. Some people on the forum may not recall that it was basically impossible to keep a goni alive. Anyway, worth a read.
The Coral Whisperer: Goniopora Revisited: If We Could Keep It Alive, Do We Really Want To? High Levels Of Toxicity In Goniopora And Other Hard Corals
Eric discusses the potential for high levels of toxicity in Goniopora.
reefs.com