Wow, love the derasa.
As to your question though ... nope, not all anemones split. Whether yours will is a definite ..... "maybe." Some ritteri's have been known to split, but it's a rare occurence compared to BTA's.
The only way to know for sure if you have a splitter is if it itself comes from a known splitter.
PS. Told ya it wouldn't stay down there ....
Really nice anemone though. You should try to make the top of the coral bommie an ideal home for it.