Pond pump is sucking up the liner

[BriMo]

I have an old cement pond with waterfall and have updated the pond in the last 5 years due to cracks in the cement. Recently my pond pump is beginning to suck up the pond liner, pushing the fish and lily pads out. I’ve changed water pumps, raised the pump on a small bucket, not sure what to try next.

 

[j.w]

@BriMo
Not sure what you mean by sucking it up?

 

[brokensword]

lay down some heavy rocks/concrete slabs around the pump, which should be 12" above the bottom.

 

[Lisak1]

What in the world? How powerful is your pump?? I've never heard of a liner being sucked up by the pump!

 

[Mmathis]

Hello and welcome!

Not sure what is going on, but I’ve never heard of a pump sucking up a liner. Are you sure that is actually what is going on, or could you be having water under the liner that is pushing the liner up?

 

[combatwombat]

Hello and welcome!

Not sure what is going on, but I’ve never heard of a pump sucking up a liner. Are you sure that is actually what is going on, or could you be having water under the liner that is pushing the liner up?

Same thought. Does the liner go back down once pump is turned off?

 

[TimL94]

Sounds more like water is building up under the liner and lifting the pump as opposed to the pump sucking the liner up

 

[poconojoe]

Interesting.
If you sat the pump on a bucket, how would it suck up the liner?
I'm also thinking water hippo.
I'll follow...

 

[BriMo]

The pump pulls the liner off the bottom of the pond and it rises to the top of the surface. I’ve tried setting the pump on an inverted pot in the pond, so that was 12” off the bottom, unfortunately not successful. The liner only rise up when the pump runs for over 2+ hrs. I currently have the pump on a timer so it will only run for 2 hrs and not cause any problems. Pump is aqua pulse 2000gph

 

[BriMo]

The pump pulls the liner off the bottom of the pond and it rises to the top of the surface. I’ve tried setting the pump on an inverted pot in the pond, so that was 12” off the bottom, unfortunately not successful. The liner only rise up when the pump runs for over 2+ hrs. I currently have the pump on a timer so it will only run for 2 hrs and not cause any problems. Pump is aqua pulse 2000gph

Interesting.
If you sat the pump on a bucket, how would it suck up the liner?
I'm also thinking water hippo.
I'll follow...

I think the pump eventually moves off due to the movement in the water

 

[BriMo]

Same thought. Does the liner go back down once pump is turned off?

Yes, it does

 

[poconojoe]

Something surely doesn't make sense. With all the weight of the water bearing down on the liner, how could a pump pull a liner up?
I say no way on this earth... something else is going on.

Plus, the input or suction of any pumps I've seen is never on the bottom. It's usually on the sides and top.

To make it even more puzzling, the liner and pump are forced to the surface....huh? Again, no way.
I'm not saying it isn't happening, it just not the suction of the pump doing it.

And it only happens when the pump is running?
Somehow the pump is pumping water under the liner.
What is the route of the hose from the pump output?
Could there be a leak in that hose near the edge of the liner causing water to leak down between the liner and the ground causing a water hippo?

A water hippo is when water builds up under a liner forcing the liner up like a big bubble. That would surely lift your pump up, no problem. You might find your pump displaced. Not sitting where you put it because it was pushed up and maybe even tipped over.

Thoughts?

 

[brokensword]

Try running the pump with the discharge hose unattached, essentially turning your pump into a fountain. See if it still sucks the liner. If it does not, then you must have some sort of issue with the water along the tubing pathway, most likely after it leaves the pond.

 

[poconojoe]

Does the liner "fall" back down when the pump is turned off or does it take hours to flatten out?

If it takes a long time to flatten out, you can bet there's water under it. It will take a while for the water to seep into the ground.

If it falls back quickly, then there is a void under it.

Good idea! Disconnect the output hose...

Try running the pump with the discharge hose unattached, essentially turning your pump into a fountain. See if it still sucks the liner. If it does not, then you must have some sort of issue with the water along the tubing pathway, most likely after it leaves the pond.

 

[Mmathis]

Anxiously awaiting the outcome of this one.