If you look under the outflow I have a 300gal/h powerhead moving water along the back glass. All the rock is very steady and solid (I made sure of that) there might be a few peices that are relying on another to hold them in place but I made sure that they were not woobly. I am also sitting on the fence with the light thing so they are off for most of the day and maybe on for 4-5 hours at night hoping that there is enuf light to keep stuff alive but not enuf for an alge explosion
