all caulerpa algae and most algae for that matter can
go sexual, even chaeto. caulerpa will do it more readily,
but as long as all the algae can get light and it has a food
source, it shouldn't go sexual. basically all that means is
trim it regularly and feed the fish and it should do fine.
you may want to isolate it though, as many people dislike
it overgrowing their reef.