If it is white w/ blue tips I would be pretty certain it's a crispa, that is very typical.
Malu have much shorter tentacles and the colors are brighter and go all the wat through tents usually, and usually they have rings around tents.
Malu are a good bit smaller than crispa when full grown, 8-10" as opposed to 2"
Slightly less light needy, less flow, low laying in sand bed.