The number of holes depends on drain size and pump output. It's hit or miss on the number of holes required. I drill new ones until the sump stops running dry during normal operation. Usually, a hole count comparable to the number of weir teeth gaps will work. I never thought to take pics of holes draining water but, I think you can imagine the outcome. Holes below the weir teeth = water goes out the holes instead of through the teeth.
Advice for lowering overflow teeth
- Thread starter Natalie
- Start date
Sorry I think my question was misunderstood. I meant, in the overflow box what is the purpose of the standpipe, as seen below:
The tank I have just has the drilled hole in the bottom of the chamber but no standpipe. I'm guessing now that maybe the standpipe is needed to quiet the water flow? Otherwise you'd hear the water gushing down all the way to the bottom of the chamber constantly?
The tank I have just has the drilled hole in the bottom of the chamber but no standpipe. I'm guessing now that maybe the standpipe is needed to quiet the water flow? Otherwise you'd hear the water gushing down all the way to the bottom of the chamber constantly?
Ah, ...now I see. Larger overflows may have an extra pipe/bulkhead for passing wiring. That type of standpipe is to raise the water level in the media chamber. Basically, the wet part of the wet/dry filter. It's design may help quiet the overflow, too.
