Lowering your pool doesn’t take a special pump — just a garden hose, gravity, and the right valve setup. Here’s how to set up a siphon, why you turn the pump off and pull only off the main drain, and how to do it without damaging the pool.
This guide is for lowering the level or a partial drain — the everyday reasons below. A completely empty in-ground pool can float out of the ground or crack from groundwater pressure, and a vinyl liner can shrink and shift. If you need the pool fully empty, that’s a job for a pro who can manage the hydrostatic pressure — call us before you do.
A few inches off the top, or a partial drain — these are the common reasons a Florida pool owner reaches for a hose.
A Florida downpour can push the water over the skimmer mouth, so it stops skimming. Siphoning a few inches back off gets the skimmer working again.
High CYA (stabilizer), salt, or total dissolved solids can only come down one way — replacing water. You drain part of the pool and refill with fresh.
Replacing a light, patching the liner, or acid-washing the surface all need the water dropped below the work area first.
Ahead of a big storm, lowering the level a bit leaves room for heavy rain so the pool doesn't overflow onto the deck and equipment.
Fill a hose completely with water, keep one end submerged in the pool, and run the other end to a spot lower than the water surface. Gravity pulls that lower column down and drags the whole pool along behind it — no pump, no power.
The only catch: the open end has to sit below the water line, and the bigger that drop, the faster it flows. If your yard is dead flat with nowhere lower to send it, you’ll need a submersible pump instead.
Pools pull water from two places: the skimmers at the waterline and the main drain on the deep-end floor. To take the level below the skimmer, you have to draw from the bottom — so close the skimmer valves and open the main drain all the way.
That keeps the water dropping past the skimmer (which would otherwise suck air and break the siphon) and stops the pump from running dry. Always shut the pump off before you move any valve — running it against a closed line will wreck it.
Seven steps, start to finish — from shutting the pump down to balancing the fresh water on the way back up.
Shut the pump down at the timer or breaker before you touch anything. As the water drops below the skimmer, a running pump pulls air and runs dry — which burns up the seal and impeller. Nothing on the equipment pad should be running while you drain.
On the suction side of the pad, turn the skimmer valve(s) fully closed and open the main-drain valve all the way. The skimmer can only pull water down to its own mouth; the main drain sits on the deep-end floor, so drawing only off the main drain is what lets you take the level lower — and it keeps a siphon from breaking when the water passes the skimmer.
A siphon is pure gravity — water only flows if the hose's open end is lower than the pool's surface, and the bigger the drop, the faster it runs. Choose somewhere legal and safe to send it (more on that below), well away from the house, plants, and your neighbors.
Fill the whole hose with water so there's no air left in it — air won't siphon. Either submerge the entire hose in the pool until the bubbles stop, or screw it onto a spigot, run it full, and cap the end with your thumb before you move it.
Keep one end underwater at the deep end (near the main drain) and carry the capped end down to your lower discharge point, then let go. Water should start flowing on its own. Weight or tie the pool end so it stays submerged at the bottom and can't slip out and break the siphon.
A garden hose moves water slowly, so a real drop can take hours — check on it, don't leave it running overnight. Mark your target (just below the tile, below the skimmer, or your dilution line) and pull the hose the moment you hit it so you never run the pool dry.
Top back up with fresh water, reopen the skimmer valve(s), and prime the pump before you restart it so it doesn't run dry on startup. Then re-test and balance chlorine, pH, alkalinity, and stabilizer — fresh fill water changes all of them.
Pool water isn’t garden water. Where you send it matters — for your lawn, your neighbors, and the local code.
Many municipalities want pool water sent to the sanitary sewer via a cleanout, not the storm drain. Check your local rules first — they vary by city and county.
Chlorinated water — and especially salt water — kills grass and plants, and chlorinated runoff into a storm drain is often a code violation since it flows straight to the bay.
If you're spreading it over your own property, stop chlorinating a day or two ahead and let the level drop near zero, then move the discharge around so no single spot gets soaked.
The questions homeowners ask most about lowering a pool. See all FAQs →
Yes. A garden hose works as a gravity siphon as long as the open end sits lower than the pool's water level. It's slow — fine for lowering the level or a partial drain — but it needs no pump and no electricity.
The skimmer can only pull water down to its own mouth, and a running pump will suck air and run dry once the level drops past it — which burns up the pump. Closing the skimmers and drawing only off the main drain lets you take the water lower and keeps the equipment safe.
Usually not. A fully drained pool can float out of the ground or crack from groundwater (hydrostatic) pressure, and vinyl liners can shrink and shift. Full drains should be left to a pro who can manage hydrostatic relief. Siphoning is for lowering the level or a partial drain.
Slowly — a single garden hose might move only a few hundred gallons an hour, so dropping the level a foot can take several hours. A larger-diameter hose or a bigger height drop speeds it up; a submersible pump is far faster if you need it.
Somewhere safe and within local rules — often a sanitary sewer cleanout, or spread across your own property away from the house, plants, and neighbors. Chlorinated and salt water can kill landscaping and violate stormwater rules, so check your city or county guidelines first.
Yes. With the pump off, the skimmer valves closed, and the main drain open, you can run a siphon off the main-drain line at the equipment pad if the pad sits below the water line. The main drain is the lowest point in the pool, so it pulls the level down the furthest.
Whether it’s a quick lower-down, a dilution drain for high chemistry, or a full job that needs to be done right, we handle it — across St. Petersburg and the Tampa Bay area.