Pool towels live a different life from the towels in a bathroom. They go from soaked to baking to folded to damp again, sometimes four times in a week, and they carry chlorine, sunscreen and grit that plain water never fully rinses away. The result is a towel that feels stiff, smells sour the moment it gets wet, and stops drying anyone properly.
What actually stays in a towel after a swim
Pool water is mostly water, and the part that is not water is what causes the trouble.
Chlorine and the compounds it forms bind to cotton fibre. That is what gives a dry towel the flat chemical smell it still has weeks after it was last near a pool.
Sunscreen is the bigger offender. It is oil based by design, it transfers off skin in real quantity, and oil does not move in cold water.
Then there is body oil, sweat, grass, deck grit and whatever was on the concrete. A towel used as a mat collects all of it.
Salt shows up too for anyone who swims in the water as well as the pool, and salt dries into cotton as a fine crust that makes a towel feel sandy.
None of that is visible. A towel can look clean, feel clean folded in a cupboard, and still release a smell the second it gets damp again.
So the job is never really about stains. It is about getting residue out of the loops, which is a different problem and needs a different wash.
Why pool towels stop absorbing
A new towel pulls water off skin because the cotton loops stand open and the fibre is bare.
Three things close those loops. Fabric softener coats them in a thin waxy film. Too much detergent leaves residue that the rinse cannot carry away. And sunscreen oil fills them from the inside.
Once that happens the towel pushes water around rather than taking it in. People read this as the towel wearing out, and it almost never is.
Pool towels collect all three at once, which is why they lose absorbency faster than any other towel in a house.
You can test it in about two seconds. Hold a towel flat and drop water on it. A working towel takes the drop straight in. A coated one holds it as a bead on the surface.
The answer is stripping what is in the loops rather than replacing the towel. Most towels that get thrown out are perfectly good cotton with a coating on it.
Washing a stack that has been sitting
The hardest version of this job is a pile that went into a bag wet and stayed there.
Shake every towel out before anything else. Sand and grit belong on the ground rather than in a drum.
Rinse the worst ones in cold water first if they are still holding pool water. Chlorine and salt come out easily while they are wet and turn stubborn once they have dried in.
Wash hot. Cotton towels take it, and oil needs heat to move at all. A cold wash on a sunscreen towel is a wasted cycle.
Use a smaller dose of detergent than feels right, and give the load room. A packed drum cannot rinse, and rinsing is most of this job.
If the smell survives the first wash, run the load again with half a cup of washing soda and no detergent at all. That is the strip wash, and it is the one thing that reliably shifts built up residue.
Follow it with a rinse that has a cup of white vinegar in it and nothing else. Vinegar and detergent in the same cycle cancel each other out, so keep them in separate runs.
The sunscreen problem in particular
Sunscreen leaves two separate marks on a towel and they behave nothing alike.
The oil is the one that ruins absorbency. Heat and a sensible amount of detergent handle it, and nothing else does.
The other is a rusty orange stain that appears after washing rather than before, which is why people blame the machine. It comes from minerals in certain sunscreens reacting with iron in the water supply.
Treat that one cold and treat it early. A dilute solution of an oxygen based colour safe brightener, left to soak for an hour, lifts most of it.
Heat sets it permanently. Once a stained towel has been through a hot dryer the odds drop sharply, so check the load before it goes in.
White towels can take a proper soak in the same brightener overnight. Coloured ones want the shorter version and a test on a hem first.
Drying without cooking them
Towels want a hot dryer and plenty of air, and they do not want company.
Dry them on their own rather than mixed with clothes. Towels shed lint and hold water far longer than anything else, so in a mixed load the clothes overdry while the towels stay damp.
Clear the lint filter between loads. A blocked filter is why a towel load comes out hot on the outside and wet in the middle.
Pull them while they still have a trace of moisture in them and finish them on a rail. Cotton driven bone dry in a hot drum goes brittle at the loops, and brittle loops shed.
Leave dryer sheets out of any load you want absorbent. They work by leaving a coating behind, which is the exact thing you have been trying to undo.
Wool dryer balls do the softening job without the film, and they shorten the cycle a little by keeping the load moving.
Keeping them usable through a long swim season
Most of the damage happens between washes rather than during them.
Never let a wet towel sit rolled in a bag. Half an hour is nothing. A night in a warm car is a sour smell you will be chasing for weeks.
Hang each one open rather than folded over a rail in a lump. A towel doubled over dries at roughly a quarter of the speed of one hung flat.
Give pool towels their own rotation and keep them out of the bathroom stack. They are doing a different job under different conditions and they will never behave like bath towels.
Buy or set aside a couple more than you think you need. The set fails when every towel is damp at once and one gets used anyway.
Strip wash the whole set once a month through heavy use rather than waiting for them to go bad one at a time and dealing with each as it happens.
Common questions about pool towels
Why do my pool towels smell fine when dry and terrible the moment they get wet?
Because the residue causing the smell only releases when it is wet. Drying hides it, a cool wash does not remove it, and the cycle repeats. A hot wash with washing soda and no fabric softener is what breaks the pattern.
Can I use chlorine bleach on them?
On white ones now and then, and it will do nothing for absorbency, because the problem is oil and coating rather than colour. An oxygen based brightener does more for a towel and is safe on coloured cotton.
Do pool towels need washing after every single use?
After every use if they have been down on a deck or have held sunscreen, which is most of the time. A towel used once by a dry person on a clean chair can go twice as long as it dried fully in between.
How do I make a towel absorbent again once it has gone stiff?
Wash it hot with no detergent and half a cup of washing soda, then run a second cycle with a cup of white vinegar in the rinse and nothing else in the drum. Leave softener and dryer sheets out afterwards or it will close up again within a month.
The Saint Petersburg part
The swim season here runs through most of the year, so pool towels stay in constant rotation rather than coming out for three months and going back in a cupboard.
Humidity is the factor that decides everything else. Gulf air keeps a damp towel damp, so one hung inside after an afternoon swim can still be wet the following day, and that is exactly how a sour smell gets established in a set of towels.
Hang them outside in moving air where that is an option, or put them straight through a dryer rather than half drying them on a rail. The half measure is the thing that fails here in a way it would not fail in dry air.
Salt air adds a second layer for anyone who is in the water as often as the pool. Salt crystallises inside cotton, leaves it stiff, and holds moisture against the fibre, and it comes out easily in a warm wash as long as the towel has not been left to dry into a crust first.
Where a full set of towels rinses properly
Towel loads fail at the rinse, and rinsing is a question of water volume rather than technique.
The machines at our self-service laundry on 4th Street North move considerably more water per cycle than a home unit, and the drums are large enough that a whole season’s towels tumble loose instead of packing into a wet knot.
Our machines and the store are cleaned daily.
Nou wash-dry-fold service covers the everyday laundry.
For general guidance, The American Cleaning Institute publishes a fabric care guide that is a useful cross-check.
The short version
Pool towels take on chlorine, sunscreen oil and deck grit, and the oil is what closes the cotton loops and stops them absorbing. Shake the grit out, rinse anything still holding pool water, then wash hot with a modest dose of detergent and real room in the drum. Fabric softener and dryer sheets undo the work, so leave them out entirely. A strip wash with washing soda revives a set that has gone stiff and sour. Treat orange sunscreen stains cold before any heat reaches them. Dry towels on their own, pull them just short of bone dry, and never let one sit rolled up in a bag.
WaveMAX Saint Petersburg is at 11138 4th N, easy to reach from Saint Petersburg and the surrounding area. If you have a load that will not fit at home, call us at 727-800-1359.