Multi color globe urchin

[Phelansfish]

Hello! Does anyone have experience with these guys? Can 2 live in a 75g? Ive read they eat diatoms and algae of the rocks and glass, has that been your experience?
Thanks

 

[ISpeakForTheSeas]

Just an explanatory bump from me since I haven't owned one myself at this point:

The Multicolor Globe Urchin is Tripneustes gratilla, A.K.A. the Halloween Urchin or Collector Urchin.

 

[SashimiTurtle]

While I dont have one, a good friend @Saltysav96 does. Her's is a pretty decent size, probably tennis ball, and I'd limit it to one, maybe two in a pretty dirty 75.

 

[MattSG]

I have 1 in my 110-gallon softie reef. It has not caused any issues. Been in there for maybe 1 year. I cannot tell if the tank can support 2. However, I can say I have almost no coralline algae. It does not seem to like the other nuisance algae that occasionally grows throughout my tank but then again nothing does. It is one of my favorite critters. It does climb on just about everything but seems very gentle about it.