My algae is out of control, growing on rocks and the glass. so I bought a small Chinese algae eater, but he disappeared after a few days. I think the convicts had him as a snack. They are only about 3/4 inch long (there's 9 remaining). Any other options for algae control? I do have 4 ghost shrimp (still alive), but I'm sure they won't last too much longer...