I got a problem with my setup. I got a 90gal. tank and i built my stand myself.I got a reefmaster sump/refugium filter system with a hobs? overflow box. I set it up in my garage for a week so i could test the stand and plumb in my filter system. I turned on the filter pump to get things going and it ran fine(quiet, no air traps, a good flow), but the water level never settled in. It would rise, and i would adjust the shutoff valve, and it would fall. I got to the point where i was only adjusting the valve .010 of an inch at a time with dramatic results which cant be right. I went for about 8-10 hours of this on and off adjusting, and it would seem to settle for about 10-15 min. then it would gradually rise or fall. I got to tell you it was pretty frustraiting. I only had hose water in my tank, and i gave the water 5 days to warm up thinking that could have something to do with it, but still failure. I was thinking it was the pump, maybe i got a cheaper one with wider tolerences( a set rpm +/- 20 rpm or something like that). It came with the filter system, but i got 5ft. of head pressure(3000gph. at 0ft.-325gph at 5ft)possibly a turbulence problem in the pump? I dont have any experience with this kind of filter system, so i dont know where to trouble shoot other than replacing the pump. Everything else seems to be pretty basic. Before i invest in a better and bigger pump is there anything else it could be? Sorry about the long story just trying to give you all the info. i can. Anybody got any ideas?