Black coraline or something else?

[gobirds4290]

My tank is a year and a half old and I’ve got zero pink/purple coraline growth. What I do have tons of though, is this black growth that covers nearly all of my rocks. Is this coraline that’s just black or is it something else? I tried scraping it with a tooth brush and blasting it with a turkey baster but it won’t come off.

 

[Randy Holmes-Farley Verified Community Expert]

Might be a sponge. Doesn't seem likely to be coralline.

 

[keagan]

+1 encrusting sponge

 

[gobirds4290]

Might be a sponge. Doesn't seem likely to be coralline.

+1 encrusting sponge

Anything to be concerned with or try to remove? Knock on wood I haven’t noticed any negative effects with it so far

 

[keagan]

Anything to be concerned with or try to remove? Knock on wood I haven’t noticed any negative effects with it so far

If it gets stressed or starts dying off theres a chance of toxin release so run carbon if it starts declining. It looks like a cryptic sponge it's growing very low on the rocks so I doubt it'll cause any issues. It looks nice enough personally I'd keep it and monitor it.

 

[Rob A]

It's a sponge I got them all over my tanks

 

[vetteguy53081]

My tank is a year and a half old and I’ve got zero pink/purple coraline growth. What I do have tons of though, is this black growth that covers nearly all of my rocks. Is this coraline that’s just black or is it something else? I tried scraping it with a tooth brush and blasting it with a turkey baster but it won’t come off.

tHIS IA BLACK SPONGE WHICH IS UNDESIRABLE AND INJECT WITH VIENGAR WHICH WILL SHRINK IT