Plumbing a frag tank

Jruss54 · Jan 17, 2022

I am getting a frag tank that I would like to plumb into my main display. Does anyone have any recommendations on how to do this effectively? I want to be able to shut water off to the frag tank while still allowing the display to cycle water. Is the sump I have big enough to handle both?
I have 125 gallon display with a 40 gallon breeder as a sump.

Eagle_Steve · Jan 17, 2022

Jruss54 said:
I am getting a frag tank that I would like to plumb into my main display. Does anyone have any recommendations on how to do this effectively? I want to be able to shut water off to the frag tank while still allowing the display to cycle water. Is the sump I have big enough to handle both?
I have 125 gallon display with a 40 gallon breeder as a sump.

How big is the frag tank and how much room do you have left in the sump if you shut the main DT return off?

This info will be needed, as first we need to see if you can support drain back from both tanks in the event of a power outage.

If you do, then you can just setup the frag tanks as a separate system that uses the same sump.

There is also the possibility to use a drain from your dt to feed the frag tank and then have it drain into the sump. This is tad bit harder to tune for proper flow. But tuning also depends on how your DT drains. For example durso vs herbie vs bean animal

Jruss54 · Jan 17, 2022

The tank is 25x18x8. I am also attaching plumbing for my display. I think the sump may have by guessing about 5-8 gallons left.

Eagle_Steve · Jan 17, 2022

Jruss54 said:
The tank is 25x18x8. I am also attaching plumbing for my display. I think the sump may have by guessing about 5-8 gallons left.

That size looks to be about 13 gallons or so (figuring about an inch from top of tank)

If done correctly, with the frag tank being that small, you should be able to plumb it is with it's own return and it's own drain. I would suggest, creating a good siphon break on the frag return and setting the water level correctly for the overflow, so minimal water drains back from the return/overflow. For the siphon break, a small hole drilled into the loc line or whatever you use, just a hair below the waterline should do just fine. I would also run the smallest pipe you can run, still keep the flow you want, for the frag return. This will also minimize the amount of water in the piping, reducing drain back volume even more. You can also use a check valve, but they will get dirty and will need to be cleaned regularly if they are to work as intended. I never run them, as all it takes is a small piece of food or algae getting lodged in he flapper to make them not work at all.

Jruss54 · Jan 18, 2022

I received the tank. Looks like the drain in drilled on the bottom and the return top right. Drain might be an inch and return 3/4. They are different. Should I just plumb it into the sump and not mess with replumbing the display or should I replumb the display so that the return pump is kicking back to both tanks?

Lost in the Sauce · Jan 18, 2022

Single overflow hole means no emergency drain line in case a snail or algea decides to clog you up.

Seeing that, I would not have it plumbed coming out of the DT, flowing into the frag tank.

I'd set it up stand alone plumbing to the sump.