bottom drilled tank question

[phunkie99]

I got a 120 gallon tank that has been drilled in four places one overflow and three return holes I assume here is a pic.

My question is how do I make it so that when the return pump is not on all the water doesn't drain out the bottom of the tank??

Pictures always help I tend to be a visual learner.

 

[Fish_wiz2]

use a check valve or if your returns are close to the surface 1. point it so that it faces the surface to suck air and breaks the siphon 2. drill a small hole near/on the water level to break the siphon.

Mine (pointed and sucks air once power is out):

(sorry, not meant to show the output but you get the picture)
hope that helps Wiz

 

[phunkie99]

Sorry forgot to mention that the pic is just from a water test. I don't want PVC sticking up in my tank like shown in the picture. So the return lines will be coming out pretty low in the DT. I'm not real comfortable trusting a check valve since I've heard they often fail.

 

[Fish_wiz2]

<a href=showthread.php?s=&postid=14700799#post14700799 target=_blank>Originally posted</a> by phunkie99
Sorry forgot to mention that the pic is just from a water test. I don't want PVC sticking up in my tank like shown in the picture. So the return lines will be coming out pretty low in the DT. I'm not real comfortable trusting a check valve since I've heard they often fail.

Really your stuck with them if it is going to be low, i got no more ideas on how to make that happen. i mean checks aren't as bad as they sound, some swear by them while some have flooded their houses, it is up to the user.

 

[phunkie99]

<a href=showthread.php?s=&postid=14700909#post14700909 target=_blank>Originally posted</a> by Fish_wiz2
... while some have flooded their houses, it is up to the user.

or the up to the valve. I would be so paranoid always thinking Im hearing the drain onto the floor. There has to be a way to do it and still have a sump

 

[heap]

<a href=showthread.php?s=&postid=14700955#post14700955 target=_blank>Originally posted</a> by phunkie99
or the up to the valve. I would be so paranoid always thinking Im hearing the drain onto the floor. There has to be a way to do it and still have a sump

i would probably return over the top/back of the tank. i know you're wanting a low return, but the only way i know you'll get away with that is with a check valve.

if you return over the top/back of the tank, and don't use the bottom of the tank bulkheads, all you need to do to not sweat flooding your house is poke an anti-siphon hole in the plumbing at the water line.

again, not helping you much with what you're wanting to do, but i'd probably use 1 hole for over flow, the other 3 for a closed loop, and just return over the top/back of the tank.

 

[phunkie99]

<a href=showthread.php?s=&postid=14701071#post14701071 target=_blank>Originally posted</a> by heap
... i'd probably use 1 hole for over flow, the other 3 for a closed loop, and just return over the top/back of the tank.

It looks like that is what Im going to have to do.

 

[ddinox64]

Are they all the same size? Usually the overflow is bigger than returns. Closed loop is your only choice if you fear check valves.