My battle with dinoflagellates

[Razor Ramon]

I always liked emerald crabs in a small tank like yours I’d only put one .
Reefers say never trust a crab .
They are opportunist so if they run out of algae the might try something else .
All the years of having emerald crabs I have never got a gouge one .
Now hermits yea bad killed my snails just because they wanted to try a new shell then went back to there old shell . Go figure