Marcye sells the red grape caulerpa. Really cool. I had caulerpa growing like wild fire, but I put a mimic tang in there and at first even he couldn't handle it. I did one good cleanup and since then, and caulerpa growing is quickly eaten by the tang. A half hour of tugging out algae and a tang are the two best solutions I know of. Some types of snail, nudis, limpets, hermits, etc can always take care of a little algae problem.