Help on water height going over, overflow.

Chad · #1 05-30-2008, 08:08 PM

why would it be necessary to have the overflow 1.5" from the top?

mark · #2 05-31-2008, 03:28 AM

Theres' two places that can help you (here) RC drain calculator. You enter the gph and it gives the weir length with about a 1/4" over the weir lip. Other place is on RDO (download) for their Overflow calculator spreadsheet. It's for a slotted weir but if using a straight weir put number of opening as 1. Can easily play with the variables to match the height you want against flow and length.

It all seems to go back to Bazins formula Q = 0.66 x cB x (2g)0.66 x H1.5 http://www.aquatext.com/calcs/weir%20flow.htm and crank it out

Skimmerking · #3 05-31-2008, 01:41 PM

Quote:

Originally Posted by Chad

why would it be necessary to have the overflow 1.5" from the top?

No chad what I was saying is the top of you box would br around 1.5 " below the top of the tank.

Chad · #4 06-02-2008, 07:09 PM

Quote:

Originally Posted by asmodeus

No chad what I was saying is the top of you box would br around 1.5 " below the top of the tank.

I understand what you mean. I am just not sure why it needs to be 1.5" from the top of the tank. If there is such low flow going through the overflow and it being coast to coast, I would think I should be able to have it much higher..

I had figured to put it around 3/4" from the top, so I do not see the water line.