I'm an incredible novice here, but for over a year I've been able to successfully keep control of both my pulsing xenia and GSP. The GSP is limited to small rocks that I sell off as pieces, and I'm training it to crawl the back wall of my tank, where somewhere hopefully it will cover it, if I have to blade it off from the top someday that's fine, but it'll take a long time to cover 7'-24". My pulsing xenia, is isolated to 2 softball sized rocks, where occasionally I get shooters and drifters, but they're easy to snag and flush. One weird thing I noticed, the first few months of having it, it constantly wanted to spread and have drifters, but now, it barely attempts to spread out. I think I just broke its spirit, its more than happy to just be a pulsing ball.