Here is a link that shows how to do what Godbert is talking about w/the aquaclear. I came real close to doing this, but I decided just to wait and do a sump/fuge later this summer.
I have some
halimeda growing in my tank behind my rocks. My turbos and other snails leave it alone and instead keep up with the other nuisance algae on the rocks and glass. Though since it is a calcareous algae, I have to be sure to keep my calcium levels up. I have had some trouble keeping them above 350ppm, but that could be attributed to other parms in my tank.
And of course, an obligatory picture:
