Byropsis.... GGEERRRRR

[shootingstar]

A Peroxide dip would work quite well.

With rock submerged and in a bucket ( I have done it with old water from a water change on the tank) pour the peroxide in very slow a little bit at a time until you see air bubbles start to form on the algae.

Let is sit for five min. Remove the rock (swish around and pull off the lose tufts of algae as best as you can) and swish in another bucket of old tank water (might as well use it for something before it goes down the drain) and then put the rock back in the tank or your rock storage bin wherever it came from.

Works very well!