# Plumbing for tanks



## riggles17 (Jan 4, 2011)

Thinking about doing a sump system. Have planned one for awhile but never actually took on the project. Just wondering how you can figure out whether your pump isn't gonna pump enough water killing your siphon or if your pump is going to over flow the tank. Do you use certain size tubing and bigger tubing for input rather then outtake. Just trying to get an idea on how it worked. I guess my siphon would be pretty constant since my tank is drilled on the back. Do you try and estimate how much water is siphoned by the PVC compared to GPH of uour pump? Lmk please


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## 50seven (Feb 14, 2010)

riggles17 said:


> Thinking about doing a sump system. Have planned one for awhile but never actually took on the project. Just wondering how you can figure out whether your pump isn't gonna pump enough water killing your siphon or if your pump is going to over flow the tank. Do you use certain size tubing and bigger tubing for input rather then outtake. Just trying to get an idea on how it worked. I guess my siphon would be pretty constant since my tank is drilled on the back. Do you try and estimate how much water is siphoned by the PVC compared to GPH of uour pump? Lmk please


Usually in a sump system you need to have some kind of overflow for the water that exits out of the tank. it does not rely on a siphon action to exit the tank. You can use a Herbie or Durso style overflow (Google them!) or and overflow box or have it drilled right out the back of the tank. And if you don't want to drill your tank, you can build an overflow box like this.

This way there is never a siphon to break, and as long as you size your overflow big enough, (and you don't get a clog!) you dank will never overfill from you return pump. Instead it will drain into your sump only at the rate at which the return pump sends it back up. So if you have a slow pump, it will just mean that the water will exchange from DT to sump slowly. You can always upgrade the pump later.

Normally there is a weir box that the water spills over in order to get into the overflow area. This would either be a part of an aftermarket overflow box, or made custom from acrylic by yourself or someone handy  Its design is to keep fish and other stuff from flowing directly into the overflow, as well as maintaining a constant water level in the tank.

Drilling the tank is the best, and you want to ideally have 2 overflow drains in case one clogs from debris or an aberrant critter. Size it for approximately twice to three times the volume of your return pump. So if you are using a 3/4" return line, then using Pi*r squared you get .44 square inches of area. Times 3 it is 1.32 square inches, so you need 1-1/4" for your return. You can be safe and go with a 1-1/2" single drain, or a main drain of 1" or 1/1/4" with an additional backup drain of 3/4".

There's a bunch of ways of doing it, but if you're pump isn't very strong, there's no harm done. If your pump is too powerful, then you plumb a type of relief valve on your return pump back into the sump.

All your bulkheads can be purchased from Mail Order Pet Supplies .com and your PVC can be found at Home Depot or Lowes.

Hope this sends you in the right direction. Google search some more and you'll see diagrams of people who've done it before.


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## riggles17 (Jan 4, 2011)

That helps a lot thank you.


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## mrobson (Mar 5, 2011)

homedepot are useless go to lowes for your plumbing they'll have everything you need other than the bulkheads.


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## riggles17 (Jan 4, 2011)

Is Rona any good?


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## 50seven (Feb 14, 2010)

I've never seen the PVC fittings that you need at Rona. However every Lowe's does. And a few HD.

Sent from my Galaxy Nexus using Tapatalk 2


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## riggles17 (Jan 4, 2011)

Alright thanks for the help, does Lowes sell glass as well?


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