Need remote sump overflow advice, crawlspace plumbing, Bean-Animal overflow.

[BadGaskets]

I'm setting up a freshly resealed 120 gallon (4ft x 2ft x 2ft) in my living room and I very much want to put the sump in an exterior closet that's about 30 feet from the tank. The closet is part of the house but sits on a concrete slab.

The rest of the house is on a crawlspace, so the plumbing would go about 30 feet horizontally. There's about a 30" drop from the bottom of the tank to the sump.

The aquarium has 2 overflows. Each has a 1" and a 1.5" bulkhead. I want to do as silent as possible here. I want to do some sort of modified Bean-Animal or Herbie here.

I can use one of the 1" for the return pump.

So, I have a 1" and two 1.5" bulkheads to do the Bean Animal type. How should I set this up?

Should I do the full-siphon (w/gate valve) on a 1" or 1.5" bulkhead?

Flow rate will probably not exceed 850-1000 gph, this tank will be a community mix of medium sized SA cichlids and catfish.


Regarding heat loss.... I'm in toasty coastal South Carolina so I'm not worried about heat loss, the plumbing will be insulated. I currently have a 75 gallon in the external closet that I can keep heated just fine.

 

[duanes]

You don't need to use an overflow hole for a return line. Using both drilled holes, you can easily balance flow and sound with a hearbie effect, quieting most suction noise
To handle the overflow rate to, and thru my sump at about 3 ft of head, I use a 1500 gph pump, with an 8 ft horizontal run, . A 1" line could not handle the flow I feel I need for proper cycling. But since mine is outside, I don;t worry about noise.

Of course you may have sedate water fish like angels, discus or severums, that don't need quite the flow my Centrall American cichlids do
I need to use both drill holes in the tank for plumbing that moves water to the sump.
To return water to the tank I just return water with PVC, over the tank rim and surface, on the opposite side of holes to the sump.
Because my cichlids are riverine, I want the flow to run the length of the tank exiting to the sump, on the opposite end, as a laminar flow in a river runs
If that's too noisy, for your room, the return line could be placed just below the waters surface to minimize splash, and cascading noise.
If your cichlids are riverine, you may need at least some surface agitation.

Below, the space and head loss between tank and sump of the system I use.
.

 

[duanes]

One other thing I would consider, with your fairly low flow system, and that 30 ft long run, two overflow ports would add a bit of insurance, and redundancy in case one got somehow plugged, and started to overflow your tank.
All it takes is an errant snail, a dead fish, or a couple leaves to get caught somewhere down the line, and end up with a flood.
And if there are spots in the crawl space you could add clean outs, or unions, to get in between, it might be a good idea.
Even with my short runs, I like to add unions for easy access.

When I redid my plumbing back in January after tremors created leaks, I added extra unions on the overflow lines for better access.