Help Deciphering My Taylor Test Results

[labdi01]

I just moved to a house that has a pool. I'd never had a pool before - so I'm new to pools and the forum.

We opened the pool 3 weeks ago and had been battling iron. We seem to have won that battle.

Based on the advise of the experts here, I purchased a Taylor 2006 test kit. I had been depending on the pool store for my water results and acted based on their numbers (and the advice of the forum). I went to the store this morning and have those results. I also received my Taylor kit this afternoon, and just performed all the testing. They don't come close to the pool store - but I trust my Taylor more.

Here are the comparisons:

Taylor Pool Store
FC - 15 CL - 3
CC - 4.5 TC - 3
pH - 7.2 pH - 7.2
TA - 60 TA - 130
CA - 50 CA - 50
CYA - 50 CYA - 100

I'm fairly confident I used the Taylor test correctly. Sometimes their descriptions of color isn't exactly what I got. In those cases, adding more of the reagent that was to change the color didn't make a difference. (The chlorine diff makes sense to me because I shocked w/ 2# cal hypo after I got their numbers - the rest doesn't make sense)

Anyway - based on these numbers, it looks like I have a FC/CC issue?

Based on other posts I'd read, I'm guessing I have to keep adding bleach until the level holds (with a 1-2 ppm buffer) overnight and CC goes down to 0.5?

I'm just not sure how to approach this. Do I try to keep it at it's current level of 15? How often throughout the day should I test the level? How much bleach vs. ppms lost should I add? Will my other numbers fluctuate because of this process?

Any help for this ignoramous would be greatly appreciated!

[Poconos]

As you found out the CYA test is very subjective. I usually use a white fluorescent desk lamp to illuminate a white piece of paper, look through the column of liquid in the tube. Add solution until the black dot just disappears. This usually agrees pretty close with doing it in direct sunlight but is more consistant. If it is 50 that's a good number. I'd ignore the TA for now and test that later after you bring the FC down to maintenance level after you've gotten the CC down to zero. You're CA is low enough so keep using the cal-hypo.
Al

[labdi01]

So keep using cal hypo until I maintain a 15 overnight and CYA is 0?

How often during the day should I be testing/adding - and do you have rough dosage/ppm lost?

Thank you so much for your time and advice.

[AnnaK]

What kind of pool do you have and how many gallons?

If your Taylor results are correct you do seem to have a nascent algae bloom happening. That would be the most obvious reason for the high CC. How does your water look?

In a non-SWCG pool with 50 ppm CYA your minimum FC should be 4, target 6, shock 20. This means you should add enough bleach for your volume of water to reach and stay at 20 ppm FC until your overnight FC loss is 1 ppm or less. The Pool Calculator can help you figure out how much bleach you'll need to add.

With which of the color tests did you have a problem?

The FC test is a color/no color test process: you add the DPD powder to your sample, which will turn pink, then add the FAS reagent until the color clears completely. To test CC you add 5 drops of reagent to the sample you've just tested for FC. If it goes pink, you add a second reagent dropwise until it becomes colorless again.

The pH test does require color comparison which can be tricky depending on your light source. It's best done in indirect light (not bright sun) while holding the comparator tube against a white background. Your pH of 7.2 is a smidgen low. If it were my pool I would add some borax or washing soda to bring it to 7.5

The TA test titrates a treated sample toward a color change. You'll go from a rich green to a grey and move toward red. It's "red" when the red doesn't change with the addition of another drop—you'll know it when you see it. You record the last drop which produced a color change. In reality, whether you counted 7 drops or 8 drops is not all that critical. My pool, for instance, is just as happy with TA at 70 as it is with TA at 100.

Can't address the calcium test since I don't do it with my vinyl pool.

I would run the CYA test again because the difference is significant and the issue could be critical. If it's 50, you're on the upper end of the scale and need to stop using products which contain CYA, such as stabilized chlorine pucks or granules. If it's 100 we need to talk about ways to reduce that concentration.

[labdi01]

Hi Anna -

Wow - great info.

I suppose I should have given pool stats to start - I'm sorry about that.

I have a 24' AG (13.5+K gals) with a vinyl liner. I utilize a sand filter with DE in it (in addition to sand, not instead of).

The water is clear with no color whatsoever (other than staining on the liner from iron issue we started with).

The tests that had the color variations were TA and CA. Red vs. Magenta and indigo/purple vs. blue. More drops did not change it.

I did CYA twice here today the first was 40 (couldn't see dot at all); second was 50 (could see dot if you really tried).

I haven't used pucks in 3 days. I used cal hypo today to shock (pool store said I had 5 ppm iron - so I shocked to shake them out of hiding in order to filter them out). Prior to that was bleach, while we filtered iron (homemade filter and DE - worked magically).

[AnnaK]

Thanks for the pool stats. If you have the ability to create a signature block (via the UserCP in the left corner of the forum menu bar) it's always helpful to put pool specs in it. That way we won't have to ask all the time. Me, I have a very short memory.

You can skip the CA tests. You don't need to worry about CA in a vinyl pool unless your fill water is very hard. But, since you reported CA=50, it isn't, so you're good without testing for that.

Your CYA test results confuse me. At 40 you couldn't see the dot but at 50 you could, a little? It ought to be the other way around. Next time you test, start the CYA process first and be as precise with your sample size as you can be. Pour the sample in, add the reagent, shake for 30 seconds. Let it sit 3 minutes, shake it up real good again, then do the spot test. The melamine takes a while to react with all the CYA to produce the cloudiness.

On the TA test, when you get magenta you're almost there. With TA=60 you'd be just one drop away from red. Don't count the drops that produced no further color change, and be sure you swirl between each drop until you get the hang of testing. I'll admit to not swirling until after the 4th drop, bad bad BAD! But then again, I know pretty much what my water chemistry is and so I tend to get a little lackadaisical.

Homemade filter? Tell! Or have you posted about that already?

[labdi01]

You're so funny!

About the CYA test, the more water you pour into the comparison vial, the lower your CYA is. So, at 40 I saw no dot - at 50 I could make it out if my life depended on it.

I didn't let it sit 3 mins. Just followed directions and shook for 30 seconds. I'll do another CYA with the 3 min-wait. Lordy I hope it's not 100! We have iron like the Navy! Would hate to battle THAT again!

With TA - I added 3 more drops - no change. I'll add more next time (too dark outside now).

Just did new FC/CC (flashlight). FC=15.5/CC=4 (added another # 52% cal hypo - will check before bed in 1 hr - is that sufficient? one hour after adding)

Homemade iron filter is described under Metals forum from "New Pool Owner with High Iron Manually Removing Iron" - but I'll save you the trouble of reading it all.

Opened pool, previous owner left 1.5' of water, we filled with well - it's FREE (knowing there was iron - but not knowing it would muck up a pool). Hired someone to come show us how to open/operate a pool. She shocked. Swimming pool-turned-cesspool. Didn't know about Pool Forum. Went to Pool store. Bought $140 in sequestrants. Got pool clear with green tinge (residual iron). Followed advice on PF and sanitized with 6 gals of bleach. Opaque brown again. Ready to tear it down (seriously)!!!!!! Made a homemade filter out of FreshStep cat litter bucket with lid. Drilled holes all over bucket (if you use this idea, don't drill holes in bottom like we did). Get a sump pump. Take a short section of hose (12-16") with an end that will fit snugly on the output of the pump (we used a section of our pool vac. The hose comes in short sections). Fill your bucket with quilt batting. I got it from Walmart in the craft section. It is packaged similarly to your Sunday paper on a rainy day - and looks similar, where it's rolled. When you open the package, take the batting out and unravel it It spreads out like a queen-sized blanket. Bunch it up and 'swirl' it around your bucket. Then make a well in the center. Make a hole in the lid of your cat litter bucket (we cut an X and pushed down the sides). Now force the other end of the hose that's on your sump pump into the lid of the bucket. Put the lid back on the bucket (make sure it's tight). Lower both into the pool - turn the pump on and let it run for at least 12 hours (no matter how brown your water is). It captures all particulate iron (even when your pool looks clear, it continues to collect iron). We had to run it for 72 hours. Hosed down the batting every 12 hrs and backwashed the sand filter when required (when output was weak). We hung the batting over the side of the deck to clean Start cleaning at the top of the batting, and you can see the iron run through the batting, easily out the bottom. It's crazy! Someone else read my post and used it and rallied for it as well. SO much easier than sequestrants - they're NOT cheap! $20/quart and I needed 6 to start, not to mention every time I have to fill or shock. No thanks.

[polyvue]

With TA - I added 3 more drops - no change. I'll add more next time (too dark outside now).

I responded to your concerns about CH and TA end-point colors in the following thread

http://www.poolforum.com/pf2/showthr...?t=9765&page=2

Magenta may indeed be the appropriate end-point for the TA test.

[labdi01]

Thank you all so much for the fabulous, detailed information.

Anna - I did the CYA test again this am. I filled the bottle with water and solution, shook it for 30 secs and set it aside. Then, unfortunately, I was pulled away and the solution sat for 13 minutes. ugh. I did the test anyway - and now CYA reads 30. Think that's reliable after 13 mins?

On the FC/CC front, the Pool Calc you lead me to (thank you so much - that thing is COOL) suggested I add another # of cal hypo last night (so I did) - fell asleep before I could test levels after that application. This am, FC was 19.5 (vs 15.5 prior to cal hypo last night) and CC is 3.5 (vs 4.5 last night). Hopefully, that's a sign toward progress, but I know how these numbers can fluctuate. Thankfully, today is going to be somewhat cloudy, so I'll check again around Noon and then again at dinner, then just before bed.

[AnnaK]

Dianna wrote:
About the CYA test, the more water you pour into the comparison vial, the lower your CYA is. So, at 40 I saw no dot - at 50 I could make it out if my life depended on it.


Yes, of course! You're right. I screwed up. Can I please use the excuse of a pulled wisdom tooth and Darvocet to explain my confusion and error?


I did the test anyway - and now CYA reads 30. Think that's reliable after 13 mins?


IMO, yes. If I understand the chemistry of the CYA test correctly the suspension is not going to go clear in time. Just make sure you shake it before pouring it into the test tube.


With TA - I added 3 more drops - no change. I'll add more next time (too dark outside now).


Once there is no change, you're done. Adding more drops won't produce a change. Polyvue's reference to magenta is good. I see the endpoint as red but in practical terms it doesn't matter. The endpoint is when you cannot produce any further color changes with the addition of more reagent.

Keep testing and keep adding enough chlorine to maintain the shock level; eventually your CCs will disappear.

That batting filter is very creative!