Pump output line trouble Help!

[Puffersayhi]

I'm brand new to the hobby, bought a used 75G with a 20G sump. It came with pvc pipe to go from the pump to behind the main tank and over the side spraying water near the top of the waterline. The connection didn't' fit my pump, so I built my own version of pretty much the same thing. All was going well until I turned my pump off and the pump line started siphoning water out of my main tank into my sump. My sump nearly overfilled with water until I realized what was going on and broke the connections going into the tank. What can I do to stop this, or am I stuck leaving my pump on all of the time.

On a side note, I'm still cycling my tank, so no fish were harmed in the making of this post.

[MJNTWise]

Place a Check valve between the pump and tank.....

[yort265]

put a PVC check valve inline somewhere. that should keep water moving only 1 way.

[Puffersayhi]

Fast and simple responses, thanks guys.

[Denbf58]

you need to set the pump off water line do not count on ck valves they can and will fail at the worst time the depth of your return and the height drain will adjust pump off water line in the sump

[Puffersayhi]

My sump is only one compartment and I just plug in my pump and it starts. What is or how do I set up a pump off water line?

[Sk8r]

Check valves are notorious for clogging, and marine tanks have a lot of calcium carbonate that will deposit and cause one to fail.
See my note elsewhere today about a water alarm. That's a good idea.
A siphon break, (a hole that will release the pressure and prevent the pipe, when inactive, from drawing water) is safer than a check valve. Talk to your hardware store, plumbing dept, bring a diagram of what you've done, and they'll walk you through designing one. Part of the answer is a shorter intake pipe, so that if the water in the display falls below a certain level---THAT becomes your siphon break. The intake also needs to be shielded against fish.

[gone fishin]

You can drill a couple small holes just below the water line in your DT. This should make a siphon break for you.

[Denbf58]

the water adjustments are at the DT is your tank a reef ready tank or was it drilled ? the line that drains to the sump needs a hole in to break the siphon. the return (the side that pumps up to the tank) needs to be at the surface so when the pump is off it suck in air and break the siphon. what is the water level in the sump with the pump on.

[shonc182]

You can drill a couple small holes just below the water line in your DT. This should make a siphon break for you.

I think this is the best route, but remember that the holes need to be large enough to actually break the siphon (instead of just draining aerated water), but small enough they don't create a separate sprayer for your supply water. Experiment - start small and enlarge them.

[gone fishin]

I believe mine are 1/8".

[Ebisan]

Agree with the siphon break. Drill a hole slightly below water line. I have one with one. Works like a charm.

[sleepydoc]

The problem with siphon break holes is that they can get clogged if under water and tend to cause splashing and salt creep.

The best/most foolproof method is to allow enough room in your sump so that it can hold any water that siphons down before the nozzle breaks the surface and breaks the siphon in the display tank.

[ajcanale]

+1 on siphon break... as simple as it gets :)

[dkh0331]

You can drill a couple small holes just below the water line in your DT. This should make a siphon break for you.



And weekly maintenance includes taking a toothpick to make sure the holes are clear.

[keithhays]

Just raise the output of the pump into the tank to just below the surface...and drill a hole or two pointing down into the water. 1/4" drill bit should be fine. One or the other will break the siphon before you flood....also a 20 gallon sump on a 75 gallon tank is a little on the small side. I would move up to at least a 40 gallon.