Ever since I set up my tank, I have this red turf algae that my fish absolutely love. I put these rock in Corpus Christi bay for several months prior to put them fresh straight into my tank. Leave alone this algae will grow into a think mat. As it my tangs and Angels mow it down as fast as it grow. I think it is a huge healthy food source for my herbivores. The algae is resilient enough to stay alive through our the up and down of my tank. Here is a picture of this algae. When they grow in a mat, it is a bright red in coloration which is nice color on the rock.
