Is this enough flow?

[matt.radich]

I am ditching my AC50 and I am making my over overflow with a 20L sump. The pump I will be using is a Rio1700 and the tank surface will be able 3 feet from the sump. I ordered from BRS the bulkheads for the holes. I got the 3/4" bulkheads and the 35mm holesaw. Does that math add up with the account of headloss? Will the holes be able to handle about 300gph??

 

[CRW Reef]

Matt make sure you do lots of research on the hole locations for drilling a 20l. I drilled mine with intentions of doing the exact same thing as you. However after drilling and the tank running for 3 days just fine, the week bottom glass cracked and my guess was from the water and wright of the down pipe. So...I would research hole location and I would also make sure you strap all the pipes to eliminate any additional stress on the bulkheads.

Here is my journey http://www.marinecolorado.org/forums/showthread.php?15573-CRW-Reef-s-20L-Frag-Tank

 

[jagermeister]

Not knowing much about your setup, I'd guess you'll have a total headloss around 4 feet (3 feet elevation and ~1 feet friction). That'd put you at 350 gph according to your pump's curve.

That's really pushing it for a 3/4" drain hole, according to the RC calculator. I'd put a valve on your return line so that you can control the flow and dial it back if necessary.

 

[jda123]

Always one-size-up a drain line. 3/4 might do 300 once you get a few elbows in it and some slime/algae on the inside. 1" would be better.

As said above, most 20G glass will not withstand drilling - it is just too think. If you have an old school Oceanic, or some custom tank with thicker glass, then it might work out.

 

[matt.radich]

Is this enough flow?

What about drilling the the 12" side? Would it be strong enough then?

 

[matt.radich]

Is this enough flow?

An I am planning on drilling the sides not the bottom, as I have read horror stories about that haha