This type of sponge is invasive in nature, so you may need to trim it to keep it in check. It sends out thin tendrils as it spreads into neighboring corals. Reef-safe-ish.
For me, I let this stuff grow as it adds biodiversity to my reef. I enjoy seeing different sponges growing in different parts of the tank, some in full light, others in total shade. A mixture of different colored sponges is cool! Some fish - angels for example - are known sponge eaters so having sponge in your tank may provide an angel an alternate snack from the daily food you offer.