Tiny Snails All Over
 

Past week or so, i've noticed hundreds of little tiny snails crawling all over my liverock and glass.

they're white and about 2mm long.

anyone know what they are? if they're bad?

What do they look like? Pyramidellid snails are parasitic; you would find them on bigger snails or clams. Rissoids are harmless, and look a lot like Pyramidellids, do a Google to figure out the difference. Sundial snails are parasitic to Zoanthids and and a little pyramid-shaped trapdoor cover over the opening of their shell when they suck themselves in. Collonista snails look a bit like Sundial, but are harmless and related to Turbo snails.

Could be stomatella but from what you describe yours are smaller

snails
 

have you been getting egg masses on your glass in the last couple of months-if you have-congrats-your existing snails had kids

+1 Make sure that the back of your tank glass is left 'dirty' so that they grow to be healthy. You should offer to give man of them away to new reefers.

I have hundreds/thousands of collonista (I think), and if so harmless. They seem to be harmless in my tank.

+1 only in my old bow front haven't been so lucky with diverse life in my 20g anyone wanna trade 5lbs for 5lbs of your snail and brittle star filled rock :p

Oh I didn't know snails could procreate in an aquarium. If they're turbo snails (I have 10 large ones) it could get crowded in there. There's literally hundreds of them

It really doesn't happen very often. People usually mistake Collonistas for baby Turbos. Most snails go through a pelagic larval stage where it would be unlikely for any to survive long enough in a reef to actually turn into a small snail. Too many predators including filtration systems! Stomatella do reproduce in reefs though because their larval stage is very short before they go through metamorphosis which makes them more likely to survive.

The ones in my tank are way to small to see what they are. They're just small white dots