Pool turns cloudy every time after rain!
- Thread starter Isabella
- Start date
Freddie
Member
Same thing used to happen to me the rain washes in all sorts of stuff like pollen and dirt I started checking pH right after storms and adding a little shock and it cleared up way faster.
Zephyr
Member
For me it was all about circulation I used to just let the pump run normal but after a storm I keep it running longer and brush the walls to get everything moving that helped the cloudiness not settle in.
Freddie
Member
That makes sense I never thought about running the pump longer after a storm I usually just let it go on the timer but maybe that’s why it keeps looking dull the next day I’ll try brushing and letting it circulate more. thanks for the tip !
Michael Young
Member
I've had the same issue with rain! The pollen and debris seem to cause the cloudiness. After storms, I started brushing the walls and running the pump longer, and that helped a lot! Might want to give that a try.
Mason Blake
Member
This is super common after rain, even when chlorine looks fine on a test.
Rain does a few sneaky things to pool water all at once:
What usually fixes it fastest for me:
Rain does a few sneaky things to pool water all at once:
- It dilutes the chemistry, especially chlorine and alkalinity
- Rainwater is slightly acidic, which can push pH out of range fast
- It washes in pollen, dust, soil, and organics you can’t really see
- Those fine particles stay suspended until the filter can grab them
What usually fixes it fastest for me:
- Test pH and chlorine right after the rain, not later
- Adjust pH first (this is key, bad pH = weak chlorine)
- Run the pump longer than normal after storms
- Brush walls and steps to knock loose what settled
- If it’s a heavier storm, a small shock dose helps burn off the organics
- Filter condition (dirty filters struggle with post-rain debris)
- Surroundings like trees or dusty soil nearby
Abena Tesfaye
Member
That is pretty normal after rain: fine dust/pollen gets in and pH can shift, so the water clouds up even if chlorine looks fine. I usually check pH after storms, do a quick brush, and run the pump longer for 12 to 24 hours. If it happens a lot, a light post-storm shock can help too.
George Kelly
Member
Yep, I used to think rain was somehow “breaking” my pool because it looked perfect before a storm and then blah a few hours later. Took me a bit to realize rain messes with more than just chlorine, even if the test says it’s fine.
Rainwater is slightly acidic, so it can knock pH and alkalinity just enough out of balance that chlorine doesn’t work as well. At the same time it’s dumping in super fine stuff like pollen, dust, and whatever gets washed off the deck or nearby plants. That junk stays suspended, so the water goes cloudy instead of obviously dirty. My filter pressure would usually creep up a couple psi after storms, which was the giveaway that it was catching a lot of tiny particles.
What finally made it predictable instead of annoying was doing a quick check right after the rain stops. I look at pH first, because if that’s off, chlorine is basically half asleep. If pH drifted, I fix that before touching anything else. Then I run the pump longer than usual and brush the walls so the gunk doesn’t just hang out. When we were getting a lot of storms, I started using a light clarifier from aquadoc and it helped the water settle and clear way faster instead of staying dull all day.
Now it’s just part of the routine. Storm comes through, quick test, a little circulation boost, and it’s usually back to clear by evening. Before that, I’d just stare at it wondering why “good” numbers still looked bad. Anyone else notice rain messes with pH way faster than normal top offs?
Rainwater is slightly acidic, so it can knock pH and alkalinity just enough out of balance that chlorine doesn’t work as well. At the same time it’s dumping in super fine stuff like pollen, dust, and whatever gets washed off the deck or nearby plants. That junk stays suspended, so the water goes cloudy instead of obviously dirty. My filter pressure would usually creep up a couple psi after storms, which was the giveaway that it was catching a lot of tiny particles.
What finally made it predictable instead of annoying was doing a quick check right after the rain stops. I look at pH first, because if that’s off, chlorine is basically half asleep. If pH drifted, I fix that before touching anything else. Then I run the pump longer than usual and brush the walls so the gunk doesn’t just hang out. When we were getting a lot of storms, I started using a light clarifier from aquadoc and it helped the water settle and clear way faster instead of staying dull all day.
Now it’s just part of the routine. Storm comes through, quick test, a little circulation boost, and it’s usually back to clear by evening. Before that, I’d just stare at it wondering why “good” numbers still looked bad. Anyone else notice rain messes with pH way faster than normal top offs?
Amber Chase
Member
It’s kind of wild how nobody talks about what runoff is actually doing during a hard rain. I’m in a pretty open area with some bare soil behind the fence, and every time we get a downpour my pool looks a little dull even though free chlorine is sitting right where I left it. Took me a while to realize it wasn’t just sanitizer, it was the load of ultra fine debris and the chemistry shift happening at the same time.
One thing I started watching was my saturation index after storms. If rain drags pH down but alkalinity was already on the low side, the water gets a bit aggressive and seems to keep particles suspended instead of letting the filter grab them efficiently. I also noticed my filter pressure bumps up 2 to 3 psi within hours, which tells me it’s catching something. Now I’ll clean or backwash sooner than I normally would after a big storm, and I’ll sometimes toss in a small dose of floc if it’s really milky so it drops to the floor for vacuuming. Not every rain needs it, but after those windy ones full of dust, it makes a difference.
Also worth checking where your deck drains. I found one corner that was basically funneling dirty runoff straight toward the coping. Fixed that and the post rain cloudiness got way less dramatic. Pools are weird, numbers can look fine but the water still tells a different story. Anyone else tracking filter pressure as their early warning sign?
One thing I started watching was my saturation index after storms. If rain drags pH down but alkalinity was already on the low side, the water gets a bit aggressive and seems to keep particles suspended instead of letting the filter grab them efficiently. I also noticed my filter pressure bumps up 2 to 3 psi within hours, which tells me it’s catching something. Now I’ll clean or backwash sooner than I normally would after a big storm, and I’ll sometimes toss in a small dose of floc if it’s really milky so it drops to the floor for vacuuming. Not every rain needs it, but after those windy ones full of dust, it makes a difference.
Also worth checking where your deck drains. I found one corner that was basically funneling dirty runoff straight toward the coping. Fixed that and the post rain cloudiness got way less dramatic. Pools are weird, numbers can look fine but the water still tells a different story. Anyone else tracking filter pressure as their early warning sign?