I've read a few threads on here about random tiny snails appearing in a tank but they have all been freshwater tanks. My 55 gallon brackish with a salinity of 1.10 has them too. I noticed them last week and there is only a few of them. I don't even know how hey got in there because the tank has always been brackish and I've never had any snail or live plants in there whatsoever. I don't mind them I'm just curious how they got there.