Separate sump and fuge flow question...

[20 20]

I'm setting up a 125 gallon reef, in a standard All-Glass stand. Short on the inside, if ya know what I mean. I already have a 30 gallon sump, with no fuge section. The return section has a 1" bulkhead in it for an external pump, but I'm going to be using a Mag9 as an internal pump since I've already got it. I also want to set up a fuge, so I bought a 16 gallon tank, and drilled holes for two 1" bulkheads. The plan was (WAS) to put the 16 gallon next to the sump, raised up a bit so the water could flow through the two 1" bulkheads over the top of the sump into the return section. But...

There's always a 'but', eh? I put the 16 gallon in the stand next to the 30 gallon, raised it up high enough so the water would flow over the edge of the sump, and there is basically no room for the plumbing to the main tank (short stand, remember?), and also VERY little room for me to get into the fuge with my hand. So, that plan is out the window. I've been noodling over different options, different size fuge, placing the fuge external to the stand, etc, none of them good for me. Then I came up with an idea, and wanted to run it by 'the experts' (YOU!). Here's a diagram of what I'm thinking:

I'm thinking of leaving the 16 gallon fuge on the bottom of the stand, and running piping from the two bulkheads in the fuge to the low bulkhead in the return section of the sump, see the red in the diagram. That would leave enough room for the plumbing, and for me to get into the fuge when I need to. I know I'd have to have the flow slow enough for a 1" hole. Would this work? Would the water from the fuge flow well enough into the return section of the pump, even against the pressure of the water already in the return pump? I know water finds it's own level, but I'm just a bit concerned. Any opinions would be greatly appreciated!

 

[dskidmore]

I assume there's an undiagramed valve on the return line branch to the fuge? If so, it should work fine. If not, you're not going to get any pressure at the display.

May want to keep an eye on fuge water level while doing evaporation top-offs, as the flow rate will slow, but if you adjust the Fuge flow valve for the maximum depth of return section, it should be fine at all parts of the evaporation cycle.

The other alternative is to have the T on your drain line instead of the return line. Some people like having "unskimmed" water going to the fuge, although if the fuge is for nutrient removal purposes, I don't think it makes a diffrence. If the fuge is for growing pods, it might help.

 

[20 20]

Yep, there's going to be a ball valve on the line going to the fuge to control the flow, I just added it to the diagram for a bit more clarity. I don't know why I didn't think of this before, but I'll just test it with fresh water, and see what happens.

 

[20 20]

Well, I did a test. I hooked up the one 1" line as shown in the diagram, filled the fuge with water till it overflowed so about 8 inches of water was in the return section of the pump. I then stuck a MaxiJet 1200 in the return connected by a tube to the fuge, and turned it on. The 1" overflow line handled the Maxijet 1200, but barely. That's approximately 290 gph.

So, my last question is, is a flow of around 250-280 gph enough for a 16 gallon fuge in a system like mine? Do I need more flow through the fuge? Any opinions would be greatly appreciated!

 

[dskidmore]

That's more than 15x flow, I might even tone it down some. A fuge can go as low as 5x fuge volume, in your case, 80 GPH would be your minimum.

 

[20 20]

Cool, thanks for the info!