New to reefing.

[Myka]

They do add to your bioload, but not nearly as much as a fish does. There isn't really a rule. The 1 per gallon thing is a joke...they'll starve to death. Start with a couple of each type you want to try and go from there. My Astreas have been very hardy. I bought three when I first set up my 33g in Dec 06, and they're all still going strong. They are an uncommon species called Astrea caelata. To give you an idea, I have 14 snails in my 33g. I also have an Orange Lip Conch. I find my Astreas, Margaritas, and Conch do the most work. The Nassarius population rotates due to them dying off (maybe 50% per year), Cerith as well although at a lower rate (maybe 25% per year). I don't find the Nassarius do a whole lot, other than picking at uneaten fish food, but my Peppermint shrimp does just as a good a job. The Nassarius also churn the sand a bit, but I find my Conch does 10x better job of that! I won't replace my Nassarius or Cerith in the future. So here's a breakdown for you:

Orange Lip Conch - churns the sand, keeps the sand clean, cleans the lower 1 1/2" of the glass (as far as he can reach haha)

Margaritas & Astreas - I think do pretty much the same thing, which the Margaritas being a bit more efficient. They do a good job of the green & brown algaes on the glass and rocks.

Cerith - stick to the glass, and don't do a whole lot.

Nassarius - stick to the sand, and due their small size, don't do a whole lot. They do churn the sand a bit, and eat some fish food, but other critters do a better job imo.

Stomatellas - awesome algae eaters, and will reproduce in the tank. My favourites.

Peppermint shrimp - Pretty much attack uneaten fish food. Good scavengers. Often eat small aiptasia, but also ate my Stomatella snails.

Cleaner shrimp - Good scavengers, will also clean some fish of parasites.

[ElGuappo]

i do have to disagree with the choosing of snails of crabs. i have a 34 G and i have over 20 snails of 4 different types and 15 hermits of 3 different types. i have seen them hassel the snails a little but they are usually able to get away unless they fall and are overturned. i have only lost 2 margarita snails in the 9 monthes ive been set up. all were added at about the same time.

Just my opinion. i do however feed an exces of pellet food once in a while as the hermits and shrimp seem to really like it.

PS i think i have lost more hermits to hermits then snails to hermits. as the 2 billion shells in my tank arnt good enough so they fued all the time.

[Doug]

Interesting. I also never knew that about margaritas. To bad,as I find them to be a good cleaning snail, unlike so many others we buy.

[Myka]

Originally Posted by Doug

Interesting. I also never knew that about margaritas. To bad,as I find them to be a good cleaning snail, unlike so many others we buy.

Yes, it is too bad...I think they are the best algae eating snail I have! They are very active, and you don't see them in the same place for long. I keep my tank a bit cooler than the "average" reefer does, at 77 degrees, but "temperate" is much cooler than that!

[Doug]

Yes, mine is seldom over 78.5 also. I was just going to purchase some more but may look for another now.

[Myka]

Try to find some Astrea caelata:

[BigA]

Will try to get some of the snail. Still haven't decided on the hermits.

Another newbie question. Now that my live rock that I have in the tank has gone through the brown stage, it is starting to become green. a light bright green. Is this the early stages of coraline algae growth? Is it some sort of pest algae? Should I get rid of it (scrub it off) or keep it?

[naesco]

Put one or two snails in your tank as that is the maximum the size of your tank will allow as there will be insufficient food for them and they will die and pollute your tank.
Many reefers think that the hermits are killing them but they starve to death and the hermits eat their remains.

Hermits are cool but will eat the tiny critters that your coral and some small fish also eat. One will do no harm though.