Size of sump for 90 G ?

[Regal]

Hi guys, new to the forum.

I have just recently picked up a 90 G aquarium and I am turning it into a reef aquarium. I would like to do a sump for this, preferably a standard aquarium, here comes the trouble, the tank has no overflows so I will be drilling the tank myself and using bulkeads. The pump I am using is a dart pump and it is rated for 3500 gph I am dilluting the flow to roughly 2650 gph.

The real questions are, what size of bulkheads should I use for drainage from the tank to the sump, should I use two? Would a 29 gallon sump be sufficent enough for this? I am concerned that teh pump will drain the sump to quick before the bulkheads can fill it, I want the sump at a consistent level.

Thanks and happy holidays,

David

[Regal]

I was thinking I could maybe control the drainage with a shut off valve?

[Aquattro]

Ideally you want something bigger than 29g for a sump. Power outages may very well over flow the sump, depending on your drain config and sump water level. And 2600 GPH thru a 29 might be a bit much.
For my 90, my sump is 110g, but you could probably get away using a 40g.

[Regal]

Thanks for the quick response. I'll try to look for a tank during boxing day. Any suggestion on the size of the bulkheads from the tank to sump? One or two?

[Chin_Lee]

at 2600 gph, i would be most concern about water noise from the overflow and drains.
I would consider 1.5" min and possibly 2".
If I were in your shoes, I would have 2 x 1.5" holes using the herbie method for dead quiet drainage.
The good thing with the dart pump is you can restrict the output without any damage to the pump. So if the 1.5" drain cannot handle the flow (which I doubt) you can tone down the output further until it can handle it. 2600 gph is a little high for a return through the sump unless you are planning to use the flow from the return as your primary source of circulation.

[mark]

RC has a calculator for drain size, here.

Heard Skimmin's tank setup with Herbie's and is silent with a Dart and believe was flowing ~2000gpm. Check his threads but he has 2x1.5" primaries with 2x1" for the backup. He also has quite the nice sump layout.