Peppermint Snails
Hyalina albolineata
The peppermint snails are not fast movers like the turbos, but they will help to clean the glass as well as areas on the live rock. I have about 8 left in the tank.

Cap Snails
Stomatella Varia
I originally picked up 4 stomatella from Inland Aquatics and they subsequently bred by the hundreds. I had a large population in the sump for a while but the larger ones have disappeared.

They are shy and come out mostly at night to clean both glass and rocks. The cleaner shrimp will prey on the smaller ones, but I've managed to keep a large population

Purple Sea Urchin
Echinoderm
This little guy just showed up one day, and must have came in as a hitchhiker on a piece of rock. Originally he was small and I didn't worry much about him. Now his size has more then quadrupled with no end in sight. Interesting creature, and he eats algae all the way down to bare rock. In nature they live in huge colonies called "urchin barrens". Their mouth is unique and called Aristotle's Lantern. They move using a water vascular system similar to starfish.

Blue Legged Hermit
Clibanarius tricolor
This guy also came in as a hitchhiker. I've never been a big fan of herds of hermits roaming around in a tank, they are just too destructive for my tastes. This guy has taken over a peppermint shrimps former housing (the snail died in a battle with the urchin - bizarre to watch).