The skimmer and return are the two places where the liner is cut, so they’re two of the most common spots for an above ground pool to leak. The good news: many skimmer and return leaks are simple fixes. Here’s how to confirm the leak is there, what to try first, and when it calls for new parts.

Step 1
How they’re sealed

The skimmer and return each bolt through the pool wall, with the liner sandwiched between gaskets. The screws on the faceplate squeeze the gaskets tight against the liner and wall. When a gasket flattens, cracks or slips, or a screw loosens, water gets out between the layers.

Step 2
Signs of a leak

• Water on the outside of the wall just below the skimmer or return.
• Rust streaks running down the outside of the wall from either fitting.
• Soft or washed-out ground under the skimmer.
• The water level stops dropping at the bottom of the skimmer opening or just below the return.

Step 3
Confirm where it’s leaking

1. Let the water drop. Turn off the pump and watch where the level stops. If it stops at the bottom of the skimmer opening, the skimmer is the likely culprit. If it drops below the return and keeps going, look elsewhere.
2. Use leak dye. With the pump off and the water still, squeeze a little leak-finding dye next to the faceplate edges and screws. If the dye gets pulled in, you’ve found it.
3. Rule out evaporation. See Reasons Why Your Pool Is Losing Water for the bucket test.

Step 4
Fixing a skimmer leak

1. Tighten the faceplate screws. Snug each one a little at a time, working in a crisscross pattern, like tightening the lugs on a car tire. Don’t overtighten. Plastic faceplates crack easily.
2. Check for missing or stripped screws, and replace them with stainless screws of the same size.
3. Look for cracks in the faceplate and the skimmer body, especially at the corners.
4. Replace the gaskets if tightening doesn’t stop it. Lower the water below the skimmer first, and buy gaskets made for your skimmer’s brand and model.

Step 5
Fixing a return leak

• Tighten the return fitting. Most returns have a threaded nut or collar inside the pool. Snug it by hand.
• Replace the gasket if it’s flattened or cracked. Lower the water below the return first.
• Check the installation. A return installed wrong can leak from day one. See How to Install an Above Ground Pool Water Return Correctly.

Step 6
Leaks outside the wall

Water near the skimmer isn’t always coming from the skimmer itself. Check the plumbing on the outside of the pool too:

• Hose connections at the skimmer and return. Tighten the hose clamps.
• Threaded fittings. Re-wrap them with thread seal tape.
• Cracked hoses, especially after a few winters. Replace any hose that’s stiff or split.
• The pump and filter, including drain plugs and the pump lid. See Pool Pump Won’t Prime? 7 Fixes.

Step 7
When to call for help

• The skimmer body is cracked or warped.
• The liner is torn around the skimmer or return.
• The wall is rusting around the cutout. See Pool Wall Rusting?
• New gaskets and tightening didn’t stop the leak.

On our liner replacements, we never reuse old, cracked skimmer or return faceplates, so the new liner starts out with a good seal. See 7 Signs Your Liner Needs Replacing.