View Full Version : Drilled Tank with 3/4" holes for overflow

12/11/2012, 02:20 PM
Hello Reef Central folks.

Brand new to the hobby and wanted to say hello first.

I've been keeping FW tanks for many years now but I've finally made the decision to take the SW leap. I've spent the last several weeks doing as much research as possible and oddly enough about 80% of my google searches lead me to RC so I figured I might as well join in on all the fun.

Well enough rambling let's get to the actual question. My plans are to have a 40g reef tank.

I picked up a drilled 40g Breeder tank and a 20g High for sump. The tank has two 3/4" holes drilled in the bottom of the tank (EDIT: Just wanted to clarify that the bulkheads are 3/4" on the inside). I have many many questions but I'll try to keep this thread to just a few. So here we go. My plans for the sump are to have 3 chambers as follows. Chamber 1: Filter Socks, Chamber 2: Skimmer, Chamber 3: Return pump.

1.) Should I plumb both holes as outputs to feed the sump and run my return line over the rim of the tank? Or just set it up as one output one return? Would one 3/4" overflow be enough for a 40g reef tank?

2.) I was thinking about using the Durso standpipe method, good idea?

3.) What should I shoot for as far as GPH on a return pump?

4.) Should I changed anything about my sump setup? I've thinking about where I could fit in some sand, LR and maybe some algae, but I'm not sure if the sump is long enough for all of that.

Thanks in advance.

12/11/2012, 08:43 PM
I run mine with one return and one drain in the same overflow and i like it a lot. I also use the Durso overflow pipe and its super quiet. GPH you want is roughly 3 to 4 times the total volume of water. IE roughly 240 to 300 GPH should work fine. The only thing i would change about the sump if you can remove skimmerto chamber 1 to help reduce any micro bubble that your skimmer might produce so they dont make their way into your main display. I have mine setup as filter sock and skimmer in chamber 1, macro algae in 2 and return in 3. Hope this helps.

12/12/2012, 05:24 AM
Both should be drains, one gate valve controlled to run at full syphon and the second is an emergency in case the primary gets restricted. The return comes over the top or drill a third hole. Search "Herbie". Dead silent and almost fall safe.