overflow problems

[arctictwist]

I have had my overflow for a while now, and it ran great for a few months. Then it started gathering air and slowing down. Now every two to three weeks i gotta shut it down and restart the siphon by sucking all the air out of the tube....what gives?

[boilermaker1]

drill a hole in the cap so the air can get out.

[70ss]

What type of overflow?

[arctictwist]

I was thinking about doing that, and attaching a tube with a valve so i could just suck the air out. Cus if i opened a cap it would just pull more in. Its an eshopps 300 gph overflow.

[arctictwist]

any screw in valves i can use?

[mdrc]

a needle valve or any valve that skimmers use on there air lines

[BuddhaKiss]

I have the same one...well actually, two. One on my main reef and mantis tank. And...I have the same problem on my main reef. I always assumed it was due to my weak return pump (mag 2). What return pump are u using and what's the gph rating?

If you solve the issue, I would love to know.

[70ss]

How about drilling hole and epoxing or glue one of those airline connectors in the hole. You could add a Aqua lifter pump to airline or connect a regulater valve that twist open and closed to the line and a length of tubing to it and suck air out when it accumulates.

[iwishtofish]

Yes, arctictwist, definitely sounds like a reduction of flow resulting in the bubbles getting trapped in the tube. This happened to me when my return line started to grow some algae.

I would try to increase your flow rather than try to deal with the bubbles with a pump, air line, etc. You could either get a more powerful return pump (just make sure it doesn't exceed the max flow of your overflow!), or you could try getting a slightly smaller diameter u-tube.

Regardless, keeping your plumbing (including your pump intake) clear of flow-reducing algae is helpful.

While you are waiting to solve the problem "permanently," you may be able to flush your u-tube daily as I have done: fill a gallon jug with your tank water, wait a few minutes for your return pump to get your overflow back up to speed, and then pour the water back into your display tank. This speeds up the flow considerably in my overflow and flushes out any trapped air. It's a pain in the butt, and becomes helpful incentive to solve the problem!

Good luck! :)

[thecichlidpleco]

I have a old style Tunze overflow with an airline hose on the top of the u-tube, and it always loses its siphon to where I have to restart it about once a month. Learning to drill glass for overflows is one of the best things I have learned in the hobby so far.

[sjm817]

A U Tube overflow should not accumulate air as long as there is sufficient flow from the return pump. If you have you dirill a hole in the U Tube to evacuate air via an external pump you have tuned a reliable design to one that is no better than the well known problematic CPR type overflow. Try increasing your return flow. What pump and plumbing setup are you using?

That being said, the Eshopps seem to be a problematic U Tube overflow. Some people have had good luck with them, some have not. There are things about the Eshopps design that I dont like. There is not enough distance between the high and low side to provide a strong siphon. The skimmer box is too shallow, the U Tube is too short and the rear baffle is too high.

[arctictwist]

Sorry guys, i got really sick and was not near a computer for a few days.

My pump is a mag 5, and is rated at just about 300 gph with the height its pumping. Now that i look at it, it could use a clean out from algae buildup on the return. I suppose ill be cleaning everything out until i have a day to fix that problem. THat would explain why it ran well for months then started having this problem.

[doubleduece]

Maybe it is cracked at a seam and allowing air in. Happened to me once...

[Bruno3047]

I agree with the "It's the pump" guys.

[arctictwist]

No i dont think its the pump, because i have a valve to that sends water back into the return section of my sump because the pump is too powerful. So it def keeps up.

[sjm817]

Can you post pics?

[Bruno3047]

<a href=showthread.php?s=&postid=13221374#post13221374 target=_blank>Originally posted</a> by arctictwist
No i dont think its the pump, because i have a valve to that sends water back into the return section of my sump because the pump is too powerful. So it def keeps up.

I'm sure.

What I meant to say was that maybe, because of wear and tear, or dirt and debris, or algae growth, the pump's performance has declined over the last month or so, and that's why you're starting to see air bubbles accumulate in your u-tubes instead of them being flushed out by the flow.

[arctictwist]

ohhh. So then maybe i oughta clean that out as well while im in there. I hope, its not wear and tear, ive been running it for under a year!

[luntiz]

Sorry this is a bit OT, but what type of external overflow do you recommend then? I know drilling is the best bet but what if that is out of the question and I have to rely on an external box?

<a href=showthread.php?s=&postid=13199080#post13199080 target=_blank>Originally posted</a> by sjm817
A U Tube overflow should not accumulate air as long as there is sufficient flow from the return pump. If you have you dirill a hole in the U Tube to evacuate air via an external pump you have tuned a reliable design to one that is no better than the well known problematic CPR type overflow. Try increasing your return flow. What pump and plumbing setup are you using?

That being said, the Eshopps seem to be a problematic U Tube overflow. Some people have had good luck with them, some have not. There are things about the Eshopps design that I dont like. There is not enough distance between the high and low side to provide a strong siphon. The skimmer box is too shallow, the U Tube is too short and the rear baffle is too high.

[sjm817]

<a href=showthread.php?s=&postid=13222307#post13222307 target=_blank>Originally posted</a> by luntiz
Sorry this is a bit OT, but what type of external overflow do you recommend then? I know drilling is the best bet but what if that is out of the question and I have to rely on an external box?
Lifereef. They are the best overflow out there.