I had a beautiful colony about 8 years ago, and it spread to several areas in my tank. I then made the mistake of buying a very cool "jeweled star" (nardoa frianti). It ate the haliclona like it was candy. At first, I thought the sponge was abundant enough to hold its own, but I was mistaken. So the sponge eventually was all gone. And soon after, so was the star. Last year, I found some of the sponge in my overflow, and now I have 10 or 12 colonies around my tank that I propagated from the overflow. It's beautiful and an awesome color. I learned my lesson. Additionally, I think mine grows and spreads faster while I dose "Sponge Power" from Zeovit. It's kind of expensive, but after the starfish, I felt like I owed it to the sponges.