snail or limpet on glass

[planenut]

My salt water reef tank has been ignored for some time. I have simply been adding RO water to replace evaporation water along with some Calcium and nutrients. The growth on the glass in minimal considering I haven't cleand it in about 8 weeks. I notice there are a lot (14 on one end of the 75 gallon tank) of small Limpets I think. Is it normal to have this kind of growth or do you think they were already living on the rock and moved there? Size? They vary but I'd have to guess that 4-5 of the larger ones would equal the head of a pencil eraser. The smaller ones, maybe 10-12 would fit on the head of a pencil eraser.

My tank is a 75 gallon oceanic with Oceanic trickle and protein skimmer. All rock, no fish, and very few corals.

 

[impur]

Are you sure they are snails? Could they be pods? Any pics?

 

[Chasing Puck]

They most likely were on the rock, and have recently moved onto the glass because it hasn't been kept as clean lately. Limpets can grow really quickly, so it's possible they were unnoticed on the rock previously, and are now large enough to easily see. Limpets typically aren't a problem-I've found them an excellent cleaner in tanks that won't support snails (in with triggers).