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Why does the water level in my pond keep dropping below my skimmer opening?
Ask Our Pond Experts
Ask Our Pond Experts

Why does the water level in my pond keep dropping below my skimmer opening?

Asked By: Charles of Bellingham, MA

A: When your pond skimmer’s water level drops too low, it could damage your pump. That's a problem, for sure! Let's examine some reasons why the water level may fall below your skimmer opening to pinpoint the solution.

Reason #1: Wrong Pump Size

Skimmers are rated for maximum water flow. If your pump exceeds this rating, the water will leave the skimmer faster than it enters, leaving you with a low water level. Check your pump to be sure it's sized correctly for your skimmer.

Reason #2: Accumulated Debris

Is your skimmer's filter mat clogged? Nets and media pads catch most debris as the water passes through your skimmer, but some may fall to the bottom. That debris could then plug your filter mat and prevent water from getting to your pump. It could also create a mini dam, causing water to escape from other areas of your pond. When you pull out your filter pad for routine cleaning, check for debris buildup in the skimmer bottom.

Reason #3: Skimmer Height

Ensure your skimmer is set at the correct height to avoid problems with low water levels. The water line of your filled pond should be about an inch below the top of the skimmer opening. If it's lower, normal variations in the water level due to evaporation can make a big difference. Check your skimmer height and adjust as needed.

Reason #4: Too-Low Overflows

If you installed an overflow in your skimmer, ensure the overflow's bottom is not lower than the ideal water level. Otherwise, small fluctuations in your pond's water level may cause issues. Check to be sure any built-in overflows are positioned at the right height to allow water to drain from the skimmer.

Reason #5: A Leak

Dropping water levels could indicate a leak, so check around your pond for pooling water. Read How to Find & Fix a Leak for tips on how to locate and repair leaks efficiently.

Reason #6: Evaporation

Evaporation contributes to waning water levels—especially in arid regions with long, hot summers. If this is a recurring problem, install an auto-fill valve to refill your pond when it gets low. Otherwise, install an automatic shutoff switch to turn the pump off automatically when the water level drops to a certain point.

Water Garden Pump & Filter Advice

Your pumps and filters are crucial components in keeping a balanced water garden. To ensure they are running smoothly, contact us online or by phone at 866-POND-HELP for routine maintenance and troubleshooting tips.

Read more about pond pumps and filters in the following related guides:

Types of Filtration
How to Choose a Pump
Find the Right Fitting
The Best Pond Filter Upgrade Options
How to Keep Pond Filters From Clogging

Last Updated: June 5, 2024