Last year I would add a gallon to my 20k gallon pool and get 5ppm. This year, I add a gallon and get zero the next day. Add another, get 1ppm. Add another and it's 1ppm. CYA is 40. I was warned about buying the freshest chlorine possible and I think Lowe's is buying old stuff this year. In addition, can I just use unscented bleach?
Weak Chlorine
- Thread starter Jim the Pool Noob
- Start date
What is the date stamp on the chlorine that you have purchased from Lowe's? I buy from Home Depot and dig through the pallet for the freshest chlorine (they still have cases of chlorine manufactured in 2018!!). I purchased a bunch the other week with a date stamp of 19213, which is a manufacture date of @ August 1st.
I never buy liquid chlorine from anybody that keeps it outdoors. Never, ever. Walmart Great Value Bleach is almost always a better choice. Usually it is less than 2 to 3 weeks old, and is inside. Great Value 6% is probably stronger than Lowe's/HD 10% every time. Lowe's/HD from 2018 is close to 0% strength.
Or is there something going on in the water which is consuming your chlorine.
Yes, you can absolutely use unscented bleach. Make sure there's no other additives, although that's sometimes hard to tell. Regular generic cheapest bleach is typically 6% so you'll have to adjust your calculations accordingly.
But do check the date as noted above. Even regular grocery store bleach can sit on the shelf too long. Recently I needed bleach but it got late and I had no choice but to buy the only 3 bottles I could find at the open late grocery store, but forgot to check the date. Had I not tested after adding I wouldn't have realized they were weak. Once I realized things weren't right (similar to your experience), I put my nose over the bottle and there was barely any scent at all. Yeah, I realize I wasn't supposed to do that, but I did and it smelled of relatively nothing. It is said that very strong/fresh bleach smells of nothing as well, so that's not a great indicator but I do usually smell "something" with good bleach. I ended up putting all three bottles in that night just to add 4ppm.
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Welcome to the forum
Chlorine is consumed by two things......organics and sunlight. The forum is all about very precise testing. I believe if you test you FC around dusk or dark and then test it again before the sun hits the pool, you will find you are losing chlorine overnight.......that's algae.......not weak chlorine.
You need a precise kit to practice the methods we teach (either the TF-100 or the Taylor K-2006C) but they are well worth it and we'll help you understand better what is happening to your FC.
Wireform has the right answer. By far, the most common reason for that is algae, not bleach strength.
Chlorine is consumed by two things......organics and sunlight. The forum is all about very precise testing. I believe if you test you FC around dusk or dark and then test it again before the sun hits the pool, you will find you are losing chlorine overnight.......that's algae.......not weak chlorine.
You need a precise kit to practice the methods we teach (either the TF-100 or the Taylor K-2006C) but they are well worth it and we'll help you understand better what is happening to your FC.
Gentlemen, thank you for your responses. My chlorine was 19045. Super old. I will get some GV bleach after work.