Question with growth on LR

[clevan]

I've had my tank up for 2 months and water parameters are excellent, contains 30 pounds of LR (34 gallon tank), cleaning crew, clown, six line wrasse, bicolor angel. Starting to get a proliferation of a purple substance on the rocks. It was originally on 1-2 of the rocks when they were purchased but seems to be spreading....any idea what it is and do I need to be concerned?
Thanks

 

[SnowManSnow]

is it hard? it sounds like coraline algae
do some searches on google.... and c if it is what you have.

if so its a good thing.


b

 

[mr_X]

i think it's marine sponges. also a good thing.

 

[ChrisRD]

I agree, sounds like coralline - a good thing.

 

[clevan]

Looks like it's coralline, thanks guys

 

[SnowManSnow]

ding