Pool water stops at the light: the niche, the conduit, and the fix

A pool that drains down to the light and then stops has a leak at that level, and on a Florida gunite pool that is almost always the light niche or the conduit behind it. It is one of the most commonly missed leaks, because it produces no wet spot in the yard and no obvious damage.

Where the water actually goes

The light sits in a niche moulded into the shell. Out of the back of that niche runs a conduit, a pipe carrying the fixture cord back to a junction box up by the equipment or the deck.

That conduit is supposed to be sealed. When it is not, water enters the niche, finds the conduit, and runs away through the pipe. It does not soak into the ground next to the pool, it travels, which is why this leak is so quiet and why people look everywhere else first.

The give-away is the stopping level: water falls to the top of the niche or just below and then stops, because below that level there is nothing for it to get into.

Check this first (free, a day)

1. Note exactly where it stabilises. Mark it on the tile.
2. Do the bucket test to confirm there is a real leak rather than evaporation. The bucket test post has the method.
3. Check whether the rate changes with the pump. A light or niche leak is static: it loses water at about the same rate whether the pump runs or not. A change with the pump points at plumbing instead.
4. Look at the niche with the pool clear. Cracks around the niche rim, a gap where it meets the shell, or missing sealant at the conduit entry are all visible from the surface with a mask.
5. Note whether the light still works and whether it has ever tripped a breaker. That changes what we bring.

Why conduit leaks happen here

Age and materials. A great many Treasure Coast pools are twenty years and older, and the sealing at a conduit entry was never designed to last forever.

Thermal movement. The same daily expansion and contraction that opens skimmer joints works on a niche.

Renovations. A resurfacing, a tile job, or a light replacement is a common moment for a conduit seal to be disturbed and not properly restored. If your leak started within a year of pool work, say so.

Bonding and corrosion. Older fixtures and their hardware corrode, and that can open a path.

What the repair involves

Resealing the niche. Cleaning out and properly sealing the joint between niche and shell.

Potting the conduit. This is the part that actually fixes most of these: filling the conduit entry with a sealing compound around the cord so water cannot travel down the pipe. Done properly it is permanent and it does not interfere with the fixture.

Fixture and cord condition. Checked while the light is out. If the fixture or cord is in poor shape, you will hear about it, because a leak repair is a poor moment to put a failing light back in.

$300–$650 covers the great majority of these. Where the niche itself is damaged or the conduit has failed further back, it runs higher and you will get the number before anything is done. The pool light leak repair page has the detail.

The safety paragraph

A wet niche is normal and is not itself a hazard: niches are designed to be full of water. What matters is the condition of the fixture, the cord, and the bonding.

If your pool light trips a GFCI or a breaker, stop using it and have it looked at by someone qualified before anything else. That is not a leak question, it is an electrical one, and it is the one thing on this page worth acting on immediately.

Why detection first

Even when the level points clearly at the light, the flat-fee detection visit earns its money, because pools frequently have more than one leak. A twenty-year-old pool that has been losing water for a season often has a conduit leak and a skimmer separation. Fixing one and watching the pool keep dropping is avoidable.

The visit is a flat $250–$400 for a standard residential pool and produces a written report and a separate repair quote. The cost calculator prices it with the repair range attached.

What to expect on the call

Where the water stops, what the bucket test showed, whether the rate changes with the pump, whether the light works, and whether there has been recent pool work. We cover Port St. Lucie, Fort Pierce, Jensen Beach, Stuart, Palm City, Port Salerno, and St. Lucie West.