Aqua Lifter not working... possible fix/repair?


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My display tank is overflowing... Once again it's the stupid CPR overflow box having issues with moving enough water down to the sump, and even the throttled back return pump (700 gph or so, 4 feet below the return head) and a 600 gph overflow box. The aqua lifter pump no longer has suction in 1 side and return through the other side... Both are very weak, to the point where you cant even tell which side is sucking and which side is supposed to be pushing it out... I took it apart once, cleaned out any dust, dirt, salt, etc I could find, got all the water out of the little rubber plunger things and it seemed to work a LITTLE better, so i ran the tank again, next thing I know after a few hours I can hear the return pump section of the sump is gurgling and almost empty! So I had to shut it down again for the night. Does anyone have any idea how this kind of pump is supposed to work? Or any way I could repair it? Otherwise I'm going to have to drive my self up to fosters on Monday when they are open. Here is a picture of the pump with the top removed and the inner workings, the only thing that comes out is the assembly of the red plastic, black rubber diaphragms, and magnet/metal arms... If anyone has any ideas please let me know, I don't want to make my tank suffer and wait to have filtration until monday yet...

As long as you have electricity, the Aqua Lifter pump is not doing anything, nor is it supposed to be doing anything. It only serves a purpose when the power goes off, so it's not like it's powering your overflow box or anything like that.

You need to clean out your overflow box and make sure you don't have a blockage in your plumbing.
It always had a steady stream of water coming out the return side and into the overflow box. Now it doesn't even move the air bubbles out of the box. I just forced some air into it and noticed its leaking air from all around the black rubber diaphragms... I just took a hot glue gun to it and it not doesn't leak all around there anymore... I'm going to give it another shot.
The overflow box won't start with out the auqalifter pump working... thats the main problem, and if it does get going and just stops when bubbles fill up the top because the stupid pump can't move air.

This is what I ended up trying just because I have no other options really. The other idea I have is to suck by mouth enough to get the water over the back of the hang on box and then plug the hose so that it holds so no air can get back in to lose pressure and therefore siphon. I think thats the pumps problem, it wasn't even sucking hard enough to seal off the box, and you can't have a siphon with an air leak in the middle of it...
Thats why I dont like those CPR overflow boxes.
Get yourself a box that uses the U style tube.I've never once seen those break siphon.Kind of a pain to get started,but once the siphon is made,you dont have to worry about it.
It works! It must have just worn out the seal on those diaphragms and they weren't air/water tight any more... It's working like it was brand new now!
That magazine cover looks pretty High Times maybe?

I used a U-tube style overflow for over 15 yrs and never had any problems, which is why I always recommend a U-tube style over the CPR style.
I was gonna suggest replacing the air tubing. Mine used to get clogged with algae. That was always my overflow box issue. Sounds like you're in business though!
This post is very helpful because I am having the same issue right now with my CPR overflow box abnd aqualifter, but I tried using a power head iin the tank with the airline tubing going to it and either it is not powerful enough to pull the air out the overflow box or my overflow box has an air leak somewhere on the side. I am going to try to do the exact same thing as you did with your aqualifter and see how it goes.

Yes, the air is trapped in the top of the overflow, so I suppose then that must mean that there is not an air leak along the seams of the overflow box somewhere.....I think that is what you might be trying to tell me Reefrookie. If that is so then that does make sense. But I might try to seal the seams anyway just to be safe. I hope it is just that the aqua lifter is in need of being replaced.
I also checked to make sure the little air hole on the overflow was not clogged by sticking a toothpick in it and I can see it go through so it isnt that.
I'm sure you checked the vent hole for blockage on the top of the overflow. That happened to me the first time and it was a quick fix. I now keep an extra lifter on hand.

Also check for blockage in the air tubing. If you are using clear, sometimes coralline algae builds up in the tubing, breaks loose, and clogs up the lifter pump. That happened to me also so now I use black air line.

I also ran some Weld-on-3 around the inside of the overflow seams to stop a leak.

Hope some of this helps!
I also checked to make sure the little air hole on the overflow was not clogged by sticking a toothpick in it and I can see it go through so it isnt that.

I had a piece of algae move over the hole when the pump was running, and move away when the pump was off. That took me a while to figure out!!!
That does help.....thanks. I have the aquarium sealant stuff and I just ran a bead and smoothed it out around where the airline tubing goes on the overflow. I too switched to the black tubing because of the same problem with the clear stuff. I am ordering 2 aqua lifters from Foster and Smith right now so I dont have to go through this again.

Thanks again Reefrookie
Well, I put a piece of tubing on the syphon vent on the overflow and created the syphon via sucking the air out of the tube and tying a knot in the tubing and he syphon continues so I believe I can rule out break in the seam anywhere on the overflow box. I can assume, I think, that the aqua lifter has just lost it's "Mojo" and maybe it is just clogged inside the filter. I did take the filter to the sink and let it suck up freshwater and it comes out of the outlet so I am not sure. When I get the new pump and it doesnt work I am going to be pissed off because then I wont know what to do next except maybe buy another damn overflow box.