CYA Through the Roof, About to Try to Deal With it.

[Pflugerpool]

Hi folks,

Just bought my house at the end of last summer, and this is the first pool I've ever had. Fortunately TFP has been keeping me alive in the meantime. It's a 16x30 in-ground, vinyl liner. I'm running a Hawyard 1-HP single speed Superpump and a cartridge filter, with a Pentair inline chlorine feeder. I calculate about 15,000 gallons.

I've been using a $20 poolstore test kit, but I just bought a Taylor K-2006. Some of my problems being that I can't keep the pH above 7, and I've had two major algae blooms this spring already. I suspected the CYA was high, as the previous owner had been feeding trichlor pucks, plus I found a half-empty bucket of stabilizer among the supplies he'd left behind.

The water's been nice and clear for a few weeks now since the last bloom, and we've been swimming daily. My data as of yesterday is:

pH: 7.0
Alk: 110
CH: 440 (we have really hard water here)
FC: 3.0
CC: 0.5
CYA: Like I said... through the roof. The highest number the Taylor test kit will read is 100, and it's way higher than that. I'll have to try a dilution to see if I can pin it down closer.

So having been reading here for awhile, I guess I'm fixing to rent a pump and do a partial water change. I've got a 2,500 gallon rainwater storage tank in the garden I can fill up, and the rest will have to go on the grass - I'm on septic, so there's no pool drain to the sewer.

So, wish me luck... I don't see any other way to deal with it. And yeah, I'll have a pool store or someone verify my CYA numbers before I take action. Thanks for all the advice so far. I'll be hanging around!

 

[jblizzle]

Welcome to TFP!!!

How have you been chlorinating? If you are using the tablet feeder, that uses trichlor tablets which also add CYA and are very acidic which is likely the cause of your low pH.

Forget the pool store testing, they are horrendously bad especially at the CYA test.

 

[Pflugerpool]

Thanks, Jason. I just continued on with feeding Trichlor pucks. I didn't know enough at the time to do anything differently, and I've just now confirmed that my CYA levels are indeed a problem.

 

[jblizzle]

Definitely time for replacing a lot of water. Following the full ShockLevelAndMAINTAIN Process. And then switching to liquid chlorine.

 

[interpim]

I just did a drain and refill to deal with a high cya level. I bought a 1hp submersible pump from harbor freight with a 20% off coupon for $50. Getting the cya in check will definitely make life a lot easier when it comes to maintaining your pool

 

[Pflugerpool]

Yeah, I stopped at Horror Fright today too and picked this up... got 20' of suction hose and 50' of discharge hose from Northern Tool, and tomorrow I'm going to put the hurt on it. This pump is supposed to do 9,000 gph, so the 5,000 I plan to do for the first partial water change should take about 30 minutes to empty... and God knows how long to refill with a garden hose - lol! But I'm looking forward to getting on top of this problem.

 

[Patrick_B]

Welcome Pfluger from another Texan

There is a company somewhere around SA/ATX that does pool RO treatment. Saw someone post about that here last summer. Sorry, I should have saved that info. If it makes you feel better, my well water is loaded. 720-740 PPM CH. I use my softener to refill some, and keep it 600 & down...that's my goal anyway.

Have a good friend who lives around Lavernia, I love your neck of the woods! Enjoy the forum.

 

[Pflugerpool]

Welcome Pfluger from another Texan

Have a good friend who lives around Lavernia, I love your neck of the woods! Enjoy the forum.

Thanks, Brushpup!

If you're in West, though I'm about as close to you as I am to La Vernia. I'm just about a mile north of the Austin city limits.

 

[Divin Dave]

Man you arent playing around are ya?? That right there is a pump! Horror Freight or not! LOL

BTW, if you are going to maintain your own pool, get you a TF100 test kit at www.tftestkits.net You will love yourself for it in the morning!
It will pay for itself in no time.

Yeah, I stopped at Horror Fright today too and picked this up... got 20' of suction hose and 50' of discharge hose from Northern Tool, and tomorrow I'm going to put the hurt on it. This pump is supposed to do 9,000 gph, so the 5,000 I plan to do for the first partial water change should take about 30 minutes to empty... and God knows how long to refill with a garden hose - lol! But I'm looking forward to getting on top of this problem.

 

[Beens]

He's got the K-2006 already. ;-)

 

[Pflugerpool]

OK, this little 2" pump may be small as far as gasoline driven pumps go, but it's a monster for this use! I didn't even run it full throttle the whole time since I'm breaking in the engine, but when I did, I picked up the end of the discharge hose and it shook me like a rag doll. And I'm 225 lbs... This thing will move some WATER! I wish I could refill the pool the same way - I've got two garden hoses working on it now and it looks like it will be many hours. Here's the pump at work:

http://youtu.be/Ec4kfwYltrs

 

[jgofnj]

Definitely time for replacing a lot of water. Following the full ShockLevelAndMAINTAIN Process. And then switching to liquid chlorine.

Just curious, why does he need to SLAM? Because the CC is .5?

 

[jblizzle]

Just curious, why does he need to SLAM? Because the CC is .5?

The mention of major algae blooms already and the low FC with the high CYA means that there is likely still algae in the pool.

 

[jgofnj]

The mention of major algae blooms already and the low FC with the high CYA means that there is likely still algae in the pool.

Got it, thanks for the explanation.

 

[interpim]

Oh wow, what a pump! I thought my pump at 1hp was powerful when it comes to emptying a pool. I drained about 7000 gallons and it took me about 7-8 hours or so.

 

[Pflugerpool]

Well, I emptied approximately 4,000 gallons yesterday and refilled it from the municipal water supply here. And this morning, my CYA is still off the chart. I guess I'll do it again - and again, and again, until I get where I need to be. I need to get this under control pretty quickly, because I have a feeling we're going to be under Stage 3 water restrictions pretty soon, and refilling pools may be prohibited.

 

[timerguy]

What was the result of your dilution test?? You sure don't want to overshoot your reduction level.

 

[Pflugerpool]

What was the result of your dilution test?? You sure don't want to overshoot your reduction level.

A 1:2 dilution with D.I. water gives me an observed value on the comparator of 70, which means corrected for dilution, it's about 210 ppm. And that's after a 30% water change. So I don't think there's much danger of "overshooting" the reduction.

I did a control sample with D.I. water and the reagent to make sure the reagent was behaving as intended, and it was completely clear, so I expect that the results of my tests are meaningful.

 

[bridgman]

Just checking, was the 1:3 dilution 1 part pool water & 3 parts D.I. water (in which case you would multiply by 4, I think) or 1 part pool water & 2 parts D.I. water (in which case you multiply by 3) ?

Sorry if this is a dumb question, but what does D.I. mean in this context ?

 

[Pflugerpool]

Sorry, I fixed my post but not before you'd noticed my mistake! The dilution was 1 part sample, and 2 parts diluent. So my math was right, but my nomenclature wasn't.

D.I. is shorthand for "deionized water;" it's very clean water from an ion exchange column that the lab here where I work uses for dilutions and rinsing. I grabbed a little in a bottle to do my tests with.