Interesting circulation pump placement. Make sure that isn't kicking up sand on your gsp as well.
I actually had it in a different spot on the right hand side of the tank about halfway down. My LFS mentioned attaching it to the back wall and pointing it straight to the front glass which will cause the water to flow around front to back and keep the glass clean as well. I had to readjust it during my last period because I noticed a little crater in the sand close to where the green star was sitting.