Be careful with the powerheads and anything else your nem might get into. My nem was moving around a little and then one day I get a call at the store asking if I over fed the tank. I was told that my tank was all cloudy and it looked like a bunch of little pieces of food floating around. Long story short, it got into one of my ecotechs and when I got home no more nem and it put me in a downward spiral for 6 months. It devastated my tank, I think I'm finally on the upswing. Cover everything your nem might be able to get into that will harm it.