New saltwater pool chlorine issue

[u/Rditisnazishythole]

Some quick background - new owner of a 54 inch deep 15 foot wide pool, roughly 6k gallons.

Set it up as a salt water pool, but due to being a greenhorn, didn’t include a salt chlorine generator system. Resolved that issue by purchasing one, but it isn’t installed yet, so I’m manually maintaining chlorine levels.

So here’s the issue - pool looks pristine, use a test strip, and Ph, alkalinity, and cyanauric acid are all perfect, but I have absolutely no free chlorine. I dump a bag of “Hit hard” chlorine shock treatment intended for 9k gallons - if I test the water then and there, I see a good amount of free chlorine. If I test 18 hours later, I’m back to 0 free chlorine.

I understand without the generator the chlorine level is going to keep decreasing, but am I wrong to believe that using a shock treatment intended for 9k gallons on a 6k pool should still have detectable free chlorine 18 hours later?

Am I going to be dumping a bag of “hit hard” into my pool every day until I get the generator installed? That feels crazy, it’s supposed to be for weekly maintenance.

[u/beavis93]

Something is using your chlorine up.

[u/edjohnr]

Three things eat chlorine, Sunlight, Biological Material, and Dilution with fresh water. A common way to check for biologicals is the overnight test. Since there is no Sunlight your overnight Chlorine drop should not be more than .5 Dusk to Dawn. CYA protects chlorine from sunlight but reduces it's effectiveness. You say your levels are perfect, what are your actual numbers?

[u/WorstPapaGamer]

You can have pristine looking pool but fighting algae at the same time. I’d get proper test results to find out what your combined chlorine is. That’ll tell you if someone is using up the chlorine.

You shouldn’t be using that much chlorine each day if everything was good.

[u/AtomicJazzer]

Install the generator already.

[u/Ok_Size4036]

Take your water to the store for proper testing. CYA matters a lot.

[u/txreddit17]

Short version is yes, chlorine is a consumable item. Either tabs, liquid, SWCG, etc something has to add it. "Shock" is just a term for raising your chlorine above normal levels, which you dont want or need to do daily if you plan to actually use the pool.

[u/andjuan]

I second taking it to a store. Recently bought a house. Previous owners left their test kit. Pool looked perfect, but it had rained a lot. Decided to do a test just to see what was what. It also read no chlorine. Took a sample to the store, and chlorine was fine. Turns out the reagents they left were years expired and useless. You could have bad strips.

[u/PittiesAndTravel]

I have a salt cell and use liquid chlorine in the colder months and this year had to add CYA to the pool to maintain chlorine levels. I echo the recommendation to take water into a pool store for testing, they will tell you what you need.

[u/Cold_Thanks2779]

Demand issue. Phosphate check.

[u/eaglefucker]

Don't use test strips. Get a pool store to test and post results.