Overflow boxes

[colby85]

I was recently looking at setting up a sump to hide all my equipment. I was looking at just getting an overflow box as it would be way to much of a hassle to have the tank drilled. My question is how do you set up return flow to match overflow. Can the overflow box be throttled or do you have find a pump that matches it near identical/ find a pump that will pump enough and the overflow box will automatically adjust. I'm semi confused on that whole operation any input would be appreciated.

 

[Anonymous]

The overflow box should have a flow rate; how many gallons per hour it can handle. With regards to the pump, you have to factor in for head loss, or the amount of flow you lose for each foot of distance from the pump to the top of the tank. So say your overflow is rated for 600 gph. Your return pump is a mag 9 which will put out 750 gph with three feet of head loss (I'm spitballing here and know these figures aren't accurate.) The return is pushing out more wate than the overflow can handle so this can be a problem. You can always throttle back a return pump by means of a ball valve or gate valve. It's really not hard and I'm sure someone else will help out more than I have. btw, I would highly rwecommend a u-tube overflow like LifeReef. I initially had a CPR OF but it was crap. I love my LifeReef and have never had a problem with it. The one I have is rated for 700 gph and I use a mag 9.5 return. It handles it quite nicely.
http://www.reefcentral.com/calc/hlc2.php

 

[Ef3s]

If you just have a straight siphon from your tank to sump you would have to pump water bank to tank at exact rate as siphon.

If you buy an overflow box it will allow anything pumped into the tank to overflow and drain to sump as long as you're not pumping more into the tank than the overflow can drain.

 

[colby85]

Thanks

 

[metalac]

you can also have some valves in your piping. This should allow you to increase/decrease flow as needed.