potential disaster

[AndrewT]

i had this problem the first week i set my tank up and my power went out. My sump overfilled and got water in the stand and on the floor.Well i adjusted the sump water level to compensate for the water in the overflow.... however power went out a few weeks ago and i watched as the sump water level rose and rose. till it almost overflowed again. Finally i realized that my 2 locklines droping into the tank from my return pump had siphoned water from inside the tank and were pushing it in reverse back into the sump. I quickly pulled the locklines above the water and all was fine. my question is if im not home to pull them above the tank when the power goes out whats going to become of my wood floor? Is there a way to fix this and keep the locklines from siphoning water when the pump dies or shuts off?

Edited May 15, 2009 by AndrewT

[Gonzobob]

Pretty sure I've seen one way check valves for sale.

[princer7]

Is there a way to fix this and keep the locklines from siphoning water when the pump dies or shuts off?

Yes. Drill a tiny hole in the lock line just above the water level (pointed to the side - not up) so that when the water level starts to back siphon, it will start drawing air and break the siphon.

I would not do check valves.... they are subject to failure.

[ReeferMadness]

would siphon breaks on the end of the lock lines correct the problem?

^what she said

[Paul]

Oh yeah- just drill some holes in the return line - I suggest at least two, snails like to cover 'em up.

I actually have mine drilled in PVC above the water line, so it is continually squirting just a little water into the tank.

But you can drill just below the water line as well. Either way works, is nearly foolproof, and avoids water all over the

place.

Use a good drill bit, and be sure not to drill on the top of the line. The bottom or sides work just great.

[AndrewT]

im not real sure where i should drill the holes... ill post a pic in this thread of the return plumbing and locklines and maybe someone can suggest a spot. How big should the diameter of the drilled holes be?

[+mcallahan]

Oh yeah- just drill some holes in the return line - I suggest at least two, snails like to cover 'em up.

I actually have mine drilled in PVC above the water line, so it is continually squirting just a little water into the tank.

But you can drill just below the water line as well. Either way works, is nearly foolproof, and avoids water all over the

place.

Use a good drill bit, and be sure not to drill on the top of the line. The bottom or sides work just great.

My plumbing came from the factory with the hole already drilled, but it was really loud from the water squirting out so I covered it up. I've got my loclines placed just below the water line so as the sump fills and the tank level falls, they are out of the water and break the siphon.

I know I'm taking a risk as if I knocked the loclines on accident, pushing them down further I could screw up my siphon break, but I'd really have to knock them to move them that much.

[caferacermike]

You drill them right at the water line. It would be great if they were just under the water so you wouldn't have to hear it as AZ said. When your water back siphons a half inch or so then they become exposed and should break the water flow. If you have a "reef ready tank" as I do then both sets of plumbing are in the same overflow box. My first hole is drilled about an inch below the water line in my overflow. Sure that water is always being recycled back to the sump but who cares about 3g per hour of lost flow? The nice thing is that in the event of a power outage my overflow drains in about 3 seconds and exposes the hole, as opposed to the 2-3 minutes of time it used to take for tank to break it's siphon.

[AndrewT]

You drill them right at the water line. It would be great if they were just under the water so you wouldn't have to hear it as AZ said. When your water back siphons a half inch or so then they become exposed and should break the water flow. If you have a "reef ready tank" as I do then both sets of plumbing are in the same overflow box. My first hole is drilled about an inch below the water line in my overflow. Sure that water is always being recycled back to the sump but who cares about 3g per hour of lost flow? The nice thing is that in the event of a power outage my overflow drains in about 3 seconds and exposes the hole, as opposed to the 2-3 minutes of time it used to take for tank to break it's siphon.

they are under water... i have a ushape over and into the tank and then an elbow from there whch connects to the locklines. so should i drill the pvc right bellow the water line then. One or two holes and how big of a hole. i was doing what mark had said placing them one almost at the surface and one at my rock wall in the tank but even after the top one was exposed to air the one submersed still continued to siphon???? Did i do something wrong... will the holes fix this problem?

Edited May 15, 2009 by AndrewT

[chrisfowler99]

they are under water... i have a ushape over and into the tank and then an elbow from there whch connects to the locklines. so should i drill the pvc right bellow the water line then. One or two holes and how big of a hole. i was doing what mark had said placing them one almost at the surface and one at my rock wall in the tank but even after the top one was exposed to air the one submersed still continued to siphon???? Did i do something wrong... will the holes fix this problem?

Your's is exactly like mine.

I've got an 1/8" hole drilled about a 1/2" below the waterline on the side of the elbow that faces the wall. I can't even see it looking around.

When I turn off my pumps you can start to siphon and then you hear a loud sucking noise as it hits that hole and the siphon breaks. It levels out at that point.

The hole time my loc-lines are under the water, though only by another 1/2" or so. If the siphon break hole fails it will drain another 1/2" or so and will break the siphon at that point, which should be before my sump is full.

[Gonzobob]

Yes. Drill a tiny hole in the lock line just above the water level (pointed to the side - not up) so that when the water level starts to back siphon, it will start drawing air and break the siphon.

I would not do check valves.... they are subject to failure.

Ah, good to know. Thanks.

[Fishn]

this worked for me on my custom set up, but on my old reef ready setup I had to cover the exsisting hole and drill a new one lower as it was very loud.