Losing chlorine

[joecus]

Hello all, I wanted to give you guys an update on my pool. I finally got my ph up to normal range 7.2 and it's been holding steady. However, I'm still losing huge amounts of chlorine every day. For the past few days, I check in the morning and my levels are the following
cl - 10+
fr cl 10+
ph ~7.2
tot alk 120
Cyanuric acid 100

At 6 pm The Cl and Fr CL go to zero and other levels stay the same. So I add shock and the levels go up. This process has been the same for about 5 days. Any thoughts?

I use 3" tabs in my chlorinator (5 tablets) and I run filter for 8 hours. The setting on the Chlorinator is maxed out. Last year, I think I used 3 tablets and ran filter for 4 hours and that was fine. Bottom line, something is eating my chlorine. Any help would be great. Thanks.

[waterbear]

Hello all, I wanted to give you guys an update on my pool. I finally got my ph up to normal range 7.2 and it's been holding steady. However, I'm still losing huge amounts of chlorine every day. For the past few days, I check in the morning and my levels are the following
cl - 10+
fr cl 10+
ph ~7.2
tot alk 120
Cyanuric acid 100

At 6 pm The Cl and Fr CL go to zero and other levels stay the same. So I add shock and the levels go up. This process has been the same for about 5 days. Any thoughts?

I use 3" tabs in my chlorinator (5 tablets) and I run filter for 8 hours. The setting on the Chlorinator is maxed out. Last year, I think I used 3 tablets and ran filter for 4 hours and that was fine. Bottom line, something is eating my chlorine. Any help would be great. Thanks.

I am going to make a guess that you are constantly fighting a nascent algae bloom because of your high CYA and that is what is consuming your chlorine. also, how are testing because there is NO reliable way to test for high C>Ya levels and there is a very good chance your CYA is actually higher than 100 ppm. The fact that you continue to use trichlor means that your CYA is continuing to climb since trichlor adds 6 ppm CYA for every 10 ppm FC it adds.

[Watermom]

If it were my pool with a cya reading of 100 and who knows how high it actually is (like Waterbear said, can't differentiate between 100 and >100), I would do a partial drain and refill and try and get the cya down to a more manageable level. Depending on high how your cya actually is, it could take a couple of partial drains and refills. I think I would drain about 1/2 or maybe 2/3 of the water and refill and then retest and see what the levels are then. Just my opinion. At any rate, regardless of whether or not you decide to do a partial drain and refill or not, you should NOT use any more trichlor. No dichlor powder either.

[aylad]

If you decide not to drain/refill to lower the CYA, you are going to need to shock the pool to overcome the bloom that's trying to happen--but with your CYA that high, you're going to have to raise your Cl to 25 ppm to get to an effective "shock" level. Once the pool has been shocked, you can let the chlorine drift back down again, but it's going to have to stay at 8 ppm or above for the rest of the season in order to not risk more problems. That's why Watermom is suggesting the partial drain and refill--to lower that CYA so that your Chlorine levels are more manageable.

Janet

[joecus]

I'm sorry I don't understand. I am getting the cyanuric acid reading from the strips that turn color when you dip it into the pool. The cya reading I get is in the "ok" range at 100 ppm. Also, you mention trichlor, what is that? I've been using shock, chlorine tabs and sometimes bleach. Is that what you are referring to?

[aylad]

The chlorine tabs, if they're the kind that you use in a feeder, are trichlor--a form of chlorine that also contains CYA. Depending on what you're using for "shock", it's probably dichlor, which also contains CYA. Continued useage of those is why your CYA level is so high. In addition, strips are notorious for not being very accurage, so you never really know for sure how much CYA you actually have.

What the strips don't tell you is that a CYA level of 100 is "ok" IF you run your pool with a FC level of 8-15 ppm and shock up to at least 25 ppm. If you let your chlorine get below 8 ppm, you're asking for algae blooms and unsanitary water. Take a look at the "best guess table" stickied at the top of this forum--you'll see that as your CYA (stabilizer) level increases, so must your base chlorine level in order to keep your water clean. So with your CYA as high as it is, I certainly wouldn't use anymore trichlor tabs or dichlor shock--I'd switch to bleach, which won't raise your stabilizer anymore.

I also would encourage you to get a test kit of your own that is drop-based, not test strips. A good kit is key to managing a clear, clean pool with very little effort. AT the very least, I would advise you to either take a sample to the pool store to be tested by the reagent method or even to go to WalMart and get the 5-way test kit (which includes a CYA test) and test it yourself.

Eitherway, you're either going to have to up your chlorine to compensate for the high CYA levels, or drain/refill part of your water to lower them, if you don't want to fight your pool all summer.

Janet

[joecus]

OK - I just ordered a 5 part test kit. My plan is to switch to bleach until I can determine an accurate cya. At that point, I will drain if necessary. Can someone explain how my pool can be unsanitary right now? Both fr cl and cl are so high, can I use pool?

[joecus]

Thanks Janet and Watermom. - I've decided to empty the pool right after the holiday. I can't get the cya and ph stabilized. Any recommendation on the refill? Do I need to scrub the liner when it's empty? Anything I need to watch when I empty it?

[Watermom]

You do NOT want to totally empty a liner pool or you will ruin your liner. Do a partial drain and refill (maybe 1/2 to 2/3 of the water) which will get your cya level down to a more manageable level, but do NOT drain all of it!

Did you get the kit you ordered? What kit is it?

You haven't posted a complete set of current water testing results for several days. Can you do that, please? Also, please list exactly what all you have put in the pool -- meaning ingredients, not just "tabs" or "shock."

[joecus]

Ok - I got the kit taylor 2005. I just ran the tests and here are the results.
fc 5
tc 5
ph 7.8
alk 120
ca 70
cya 100+
As far as ingredients, I started the year using, powder shock with the 3" tablets. When I started losing chlorine I added about 4lbs of cyanuric acid. Then I added a algaecide to stop the chlorine loss.
Once I realized my ph was too low, I started adding borax, I would guess 15 boxes up to this point. Then I realized my cya was too high so on Tuesday, June 30, I emptied half the pool and refilled. I've been using bleach only for about a week. I'm checking the chlorine very often and adding bleach as needed. So, what do you think? Thanks for your advise.