Question about vinyl + chlorine feeder

[eskewj]

Hello,

I recently purchased a home with a pool without knowing anything about pools or taking care of them, reasoning I could learn from resources like TFP. I also purchased a book on Amazon called Pool Maintenance Made Easy by John Brace. In the book (it doesn't have page numbers!) it says "You should not use tablet or liquid chlorine with a vinyl pool. Instead use granular chlorine only." This was alarming because my setup has a chlorine feeder with tablets inside. Should I be worried?

 

[BoDarville]

Welcome to TFP!

"You should not use tablet or liquid chlorine with a vinyl pool. Instead use granular chlorine only."

Granular chlorine comes in various formulations with different active ingredients and fillers. Some granular chlorine can leave spotting on vinyl surfaces if the granules are dumped in dry (especially calcium hypochlorite - a.k.a., Cal-Hypo). So, I would ignore that book's advice.

Most members use liquid chlorine for their pools regardless of the surface. The main thing with any type of chlorine is that you must dose according to the stabilizer level (CYA) of the pool water.

Here are a couple of resources to help get you started on the right path:
ABC's of Pool Water Chemistry
Chlorine CYA Chart
How to Chlorinate Your Pool
Pool Math

 

[linen]

Welcome to tfp, eskewj

Bodarville gave you good advice and pointed you to some good pool school articles. I thought I would just mention that those pucks in your erosion feeder are continuously adding cya and that will become (or maybe already is ) an issue for maintaining an algae free pool. Make sure you read those articles Bodarv linked!

 

[eskewj]

Do folks here still use the erosion feeder to administer the liquid chlorine?

I checked my chlorine levels using the recommended test kit and it was so high that it was off the charts, even though the chlorine feeder was on its lowest setting. I thought maybe I did the test wrong, so I took it to the pool store and they confirmed it was way, way too high. Possibly the highest they've ever seen. Plus they said my CYA levels were very high because the previous owner was "buying cheap supplies from Walmart" instead of the pool store. I thought that CYA would be a good thing because the stabilizer would keep the chlorine from depleting quickly (use less chlorine) but I need to read up on that more.

Anyway, I turned off the erosion feeder, fished out all the tablets, drained the pool about 2/3rds and refilled with well water as starting over is the only cure this time of year according to the guy at the pool store. I will retest tomorrow.

 

[jblizzle]

No. you can not use the tablet erosion feeder for anything but the trichlor tablets.

Which kit did you buy? If it was one of the recommended ones with the FAS-DPD chlorine test, there is no such thing as "off the charts" It will easily measure up to 50ppm.

Trust your own testing. Check out the Extended Test Instructions and the Youtube videos linked to here: Recommended Test Kits

Also, since you are trying to learn the chemistry, here are a few good articles to start with:
ABCs of Water Chemistry
Recommended Pool Chemicals
How to Chlorinate Your Pool

 

[RobbieH]

The source of Trichlor does not matter. Any trichlor tablet will add CYA to the pool. Again, a pool store has no clue what they are talking about, or it may have been on purpose as a tactic to get you to spend more at their store.

Once CYA gets too high, your chlorine becomes ineffective. Since you are not using a salt system, your CYA should be around 30-40ppm. If you are at 80+, a partial drain and refill is in order. Note, anything over 100 is very difficult to measure, and most likely you are well over 100 if so. You can dilute your pool water 50/50 with tap water and measure CYA again, then multiply the result by 2.

The pool store got one thing right, you do need to partially drain and refill. Otherwise, I suggest avoiding their recommendations until you get the results you want here. Mixing recommendations between TFP and a pool store will not work.