Overflow box issues

I recently set up my 150, filled it with water and all the goodies, including a CPR overflow box which goes to a 30 gal sump. For the life of me i can't seem to adjust the amount of overflow with the return pump. I have valves on each and cannot seem to dial them in right....close, but not right. Obviously i should have just drilled the tank but didn't. Any suggestions? Should i drain and drill? Help! Id rather not waste 170 gal of good fresh RO/DI saltwater... it took way too long to make!!!

 

Is the overflow rated for the output of the return pump?

 

You shouldn't have any valves on the drain line . That could create a flood. As long as the return pump is sufficient you should be fine. If its to much flow for the overflow box dial it back with the valve on the return line.

 

+1

Can you post a pic of your overflow box so we can see how you have it set up? You should not need and do not want to regulate the overflow.

 

You just need a T off the return pump. The pump should be rated right at or very close to what your overflow is. The T off the retrun is to fine tune the flow.
http://www.melevsreef.com/what_sump.html

 

If your overflow is not losing siphon any water pushed through you return pump will be drained by your overflow.

 

Never ever restrict the overflow! You control the flow rate with a ball valve on the discharge side of the return pump and the overflow self adjusts to that flow.

Adding a tee to the discharge side of the return pump is not a very good idea. Centrifugal pumps draw only the watts or amps required to do the work at hand (plus a little for electrical inefficiencies) so returning flow to the sump uses more power than throttling the discharge flow with a ball valve and leads to hotter water and higher power bills. This is easy to demonstrate with a Kill A watt meter. The throttled pump wil draw less wattage than the pump returning flow and will be operating cooler. It will also last longer contrary to popular belief.

 

And just a side note: if you wanted to drain and drill, you could go get a couple of 55 gallon food safe bins and just drain your water into those.

 

WOW, and where in here does it answer his question???

 

He is pointing out that a T on the return side is a bad idea and explains why it is. It is a very informative post that will give foundation as to why NOT to do what was suggested.

As most others have posted you never need to restrict the flow of the drain. Only tune the return side with your valve and the overflow will self adjust to what is being returned into the DT. I ran a 1100gph pump on my 55 for a while, which was FAR to much of a pump for that size tank, but with a ball valve dialing it back my overflow tuned in and it worked flawlessly.