what causes my overflow to run higher than it normally would. It is almost to water level now, but isnt overflowing.....so what made it rise? Is the drain stopped up or somthing???
I just had the same issue and I pulled mine and cleaned it with a baby bottle cleaning brush and my camel bak cleaning brush. Lots and lots of hair algae was at the apex of the loop and thus causing the slow rate. I also kept my mangrove plant in the overflow box but the roots were going up the drain as well so I had to move it as well. Now the flow is back to normal.
What type of overflow are you using? I am using the lifereef with the U shaped cyphon from tank to box. It gets algae in the top of that u shaped tube going from tank to overflow box. My stand pipe has not been clogged thus far.