One other thing I'd like to add. Emerald Crabs can eat a bit of algae, just be careful when they grow in size as they might grab small fish. Also just read an article about Court Jester Gobies that apparently eat filamentas algae. They are small and great for Nano setups. I also have Sailfin Mollies ( any Sailfin Mollie can be put in saltwater by adding tankwater to the bag gradually over an hour or two). They tend to nibble on liverock at the top of the tank where they always hang out as a school, and they bring out all the other shy fish that I never used to see much of. I guess they feel safe if the Mollies are out. I also restock dwarf red leg and dwarf blue leg hermits about twice a year as a cleanup crew. I put about 50 in my 90 gallon reef tank. For whatever reason, Mexican Turbo snails just dont seem to live all that long so I've stopped stocking them. Astrea snails seem to live for a long, long time . I keep several Skunk Cleaner shrimp in a 32 gallong Biocube reef setup they seem to keep that tank very clean. I also put Nassarious snails in that tank to burrow in the shallow sandbed.