brown algea on coral rocks

[surjer]

I have a brown algea that I cant clean off of my rocks. Its a 20gal tank with about 8 fish in it and 3 ghost shrimp. How do I clean the rocks because scrubbing them with a toothbrush doesnt get them clean..

 

[toddnbecka]

Soak them in bleach (unscented) and water, then fresh water. Use plenty of dechlorinator to remove the bleach that may have been absorbed by the coral, or allow it to dry out completely before placing back into the tank.