Can't Get a Chlorine Reading

[txmom4]

We had our pool installed last summer. It has an automatic chlorinator we have set high in the summer. We shocked once a week too. Problem is, we never could keep a chlorine reading past 2 days. Then would show low or none. We have a large fiberglass pool. I take my water in to be tested and every time they say "everything looks good, you just have no chlorine". There last suggestion was to pour liquid chlorine in. We did a whole jug and it lasted about 3 days. So we put in another gallon and it lasted a week. Its a 13k gallon pool.

Any advice. Keep adding more jugs of liquid chlorine. Even in the summer, after shocking it would only last maybe 2-3 days with getting a reading. Its up to 70 degrees and my kids want to swim next month (hopefully) so we are trying to get the chemicals right!

 

[Texas Splash]

Hi TXmom and welcome to the forum! Nice to see another local here. Simply put, we are initially led to believe by installers, builders, and pool stores that certain levels (FC in your case) should be kept low at all times when that's not exactly true. Also, relying soley on the in-line chlorinator will increase your stabilizer very fast (CYA) which demands a higher FC level. Store testing is also another pitfall that can bite you in the swim trunks. In short, I would highly recommend the following Rx for your pool:
1. Get your own TF-100 (link below) or Taylor K-2006C test kit. It's EASY to do. But that's a must. I recommend the TF-100 for its value.
2. Review the TFP Pool School page (link above & below) and get accustomed to how we do things with our pools. It's very easy.
3. Review & bookmark the vital links below in my signature. Pay special attention to the Chlorine/CYA Chart as that's directly related to your situation. Again, proper home testing is key.
Let us know if you have any other questions.

 

[YippeeSkippy]

Without knowing your entire chemistry reads from a *reliable* test kit (pool stores are notoriously unreliable) so I'd venture a couple of guesses-
1) No CYA in the water to "hold" the chlorine
2) kids peeing in the pool and the pool is rife with CCs (the contaminates, aka "cooties" I call 'em)
3) Your CYA is so high that your dosing of chlorine can't keep up to be effective

We believe in *owner-testing* because you have your pool's best interest in mind...the pool store has selling as their main focus. Perhaps a reason to find problems with a pool test, huh?

Do you buy the "liquid shock" from them? Did you know you can use plain household bleach to care for your chlorine needs? H.E.B bleach tends to be cheap and readily available. With all those kids I bet you live in the grocery stores to feed that crew...just pick up some fresh bleach each time.

Test kit recommendations- they are not hard to use at all. We only trust two, the K-2006C from Taylor, or the TF-100 which also uses Taylor reagents but is a better buy.
We need to know:
FC
CC
pH
TA
CH
CYA

Then we'll be able to help you diagnose the problem better.

How does your water look? Clear? Cloudy? Green??

Maddie