Troubleshooting Leaks in Your Pond/Pondless Waterfall

Does your pond actually have a leak?

You may not realize how much water can evaporate from a pond during the dog days of summer.

The midwestern states typically lose 1 to 1 1/2 inches of water each week. In Arizona for example, it is reported that evaporation rates are in excess of 3 inch a week.

These are averages. Some ponds may not experience evaporation levels this high, while other ponds with large pumps pushing high volumes of water or ponds with multiple waterfalls and lots of cascades and splashing on rocks, have higher evaporation rates.  The larger the pump gph the more water you can lose.

Do not try to investigate a leak if the ground is wet from a rainfall.

1. The most common leak is one that is created from low edges. Here’s a little secret,99% of all leaks are not due to a hole in the liner. Settling at the pond’s edge is the most frequent cause especially in new ponds. Look around the stream and waterfall for areas that have settled. Look for wet mulch or wet gravel along the edge.

How to fix a low edge?

Simply build back up by backfilling and compacting the soil beneath the liner. Thus raising the edge of the liner above the water level.

2. Look for obstructions in the stream and waterfalls. If you have adjusted some of the rocks to improve the look you may have caused some of the water to be diverted over the liner. Also look for excessive plant or algae growth in the stream allowing water to make it over the edge. If you use Hyacinth in the biological filter, remove some occasionally as the volume of plants raises the water level and will allow some water to leak over the back or side edge of the BioFalls.

3. Can’t find the leak yet?

Shut down the pump and leave it for 12 or more hours. After 12 hours check to see if the water level has dropped. We recommend you use a small aerator to provide oxygen to the fish.

If it has dropped, you now know the leak is in the pond. If it remains the same, it is in the stream or waterfall.  Read on..

If the leak is in the pond.

Leave the pump off and wait until the water level stops dropping. This could take several days. This will determine the height of the leak. If the water level stopped below the bottom of the skimmer face plate, you can rule out the skimmer and concentrate elsewhere. If the water level is above the bottom of the face plate, you should investigate the skimmer. It may have not been sealed properly or if sytem is over 5 years old, it may be time to reseal the skimmer to the liner. But don’t tear apart the skimmer face plate yet.

If the Leak is in the Skimmer.
At this point you may want to call the contractor who installed the pond. However, if you are brave enough to search further, then read on.

Investigate the skimmer face plate without disassembling it. Simple move a few rocks around the front of the skimmer and slide you hand behind the liner. Feel for wet soil around the opening of the skimmer.

If it is dry, it is most likely not the skimmer.

–If the soil is saturated, then the face plate may NOT have been installed properly and might be the source of the leak.

–Remove the face plate, clean all of the old silicone off the liner with a plastic scrubber and refer back to the instructional manual on proper procedures for sealing the skimmer face plate to the skimmer. Use Black Silicone to seal the skimmer to the liner.

If it’s not the Skimmer.

Investigate the liner for small punctures around the perimeter of the pond where the water level has stopped.
The only way to find this type of leak is to move rocks and gravel and search by hand and eye. If the leak is found, you can fix it using the Patch Tape.

Is the leak in the Biofalls or Waterfall?

If your water level did not drop over the past 12 hours, this immediately tells you that the pond is not the source of the leak.

First, turn the pump back on and get the water flowing.
Double check that all the edges are high, and any stream liner overlaps into the pond properly. Or if you had installed with liner seams, check this area out.

Check the seal on the lip of the Biofalls. Again, simply move a few rocks and dirt if necessary to allow your hand to slide behind the liner. Feel for wet soil.

If it is dry, it is most likely not the Biofall seal to the liner.

If it is saturated, or you feel water leaking, then the lip needs to be resealed.

Cause of leaks at the Biofall seal.
1. Seal was done incorrectly or the liner was stretched or pulled too tight while setting rocks for the waterfalls. Also, after 5 years, it is possible your seal has deteriorated and needs to be taken apart and resealed.

2. Always make sure you allow some extra liner along the front of the Biofalls to prevent stress on the Biofall seal.

If necessary, reseal the Biofalls by removing the lip. Clean all of the old silicone and waterfall foam off the liner and refer back to the manual as to the proper procedure for sealing.

Still can’t find the leak!

Investigate the rest of the stream and waterfall. At this point, you should be looking for a hole in the liner.

If you have a long stream, you can divert the water using a hose and begin running water from the hose down the course 5 feet from the pond. Watch the water level, if level has not dropped then move the hose 5 feet more up the course. And you do this until you see a drop and can isolate the leak to a specified 5 foot area.

Still can’t find the leak, are you sure it was not evaporation. Just kidding, of course. It may be time to call that contractor.

Hope you find that leak!!!

4 replies
    • Michelle
      Michelle says:

      Good morning!

      Thank you for contacting! You might want to check the fittings and clamps to make sure they are secure if you have water coming from the pump. Also check to make sure the pipes are not busted.


  1. Martina King
    Martina King says:

    Maybe I didn’t explain well enough sorry for that. The top of the control panel of the aquascape when you turn the pump on water comes out of the top of the aquascape.

    • Michelle
      Michelle says:

      Good morning!

      If you would, give us a call at 877-780-1174 and we can discuss the issue you are having.



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