Whom would you trust?

[jeepers]

Thanks, Guys! Glad to hear that it sounds like I'm doing things right. Water is beautiful, I feel like I am understanding the principles of BBB, I'm getting into a testing routine and I've found and identified the Borax, Baking Soda, Soda Ash, 6% hypo, etc so I know exactly where to go and exactly how much it will cost when I need to make adjustments. I finally feel like I am being proactive as opposed to reactive with regard to my pool maintenance.

Ben, I'm glad to hear that your impression is that these tests are reasonably close. I didn't make it clear in my original post, but the biggest effect that these tests had on me was confusion about whether to continue to use my pucks. As you may recall from an earlier post, I had just purchased a 25# tub of pucks before deciding to convert to BBB so I'm trying to recoup as much of that cost as I can. The CYA from pool store #1 was in the 50s, which would make me want to stop pucks immediately. However, the CYA at #2 was only 40 which made me think that I could just continue with the pucks and just bring the pH up bit (expecting it to continue to drop is the pucks in the water).

My compromise: I've left the pucks in the water but closed down the floater a bit. Just going to watch everything else for a few weeks and make minor adjustments, as necessary.

Thanks again for all of your help!

Jim

[PoolDoc]

Personally, I'm drifting, well no, MOVING rapidly toward a high CYA / high Cl approach to pool care. If it were just me, I'd use the trichlor up, use borax to compensate for pH drift, and use the Best Guess tables to adjust chlorine levels as CYA increased.

Oh, and you'll want to keep some chlorine in the pool over the winter, so the CYA doesn't get degraded.

But, this represents a change from my original approach on PoolSolutions, and I haven't worked it out with my moderators and others yet, and there are a bunch of pages to be revised. So, this is "UNOFFICIAL" advice.

[SalemCastles]

Hi Ben,

What are you considering as High CYA? Any concerns over the toxicity of CYA?

[waterbear]

Hi Ben,

What are you considering as High CYA? Any concerns over the toxicity of CYA?

Cyanuric acid is essentially non toxic with and LD50 of 7700 mg/kg in rats. For comparison purposes baking soda (sodium bicarbonate) has an LD50 of 4220 mg/kg, table salt (sodium chloride) has an LD50 of 3000 mg/kg, Aspirin 200 mg/kg, and caffeine 192mg/kg.
This means that baking soda, table salt, Asprirn, and caffeine are progressively more toxic than CYA!

[SalemCastles]

That's good to know ...I've been called a Rat a few times.

[PoolDoc]

That's good to know ...I've been called a Rat a few times.

[CarlD]

I agree with Ben about the numbers. Here's what I saw:
Variation in the FC/TC did bounce around a bit but in EVERY test FC=TC meaning there's no CC. The difference wasn't very great either...3 to 4. No biggie.

All but one of the pH tests were within a couple of tenths--7.5, 7.6, 7.9. The 7.9 is almost an outlier but it's still not far away.

Alkalinity is also really, really close...basically the same.

The one difference was CYA being 40 in one and 55 in another--and we see such wild swings all the time. My view on CYA is I do it exactly the same way every time and use THAT as my baseline. And I always run the test twice, at least. Just pour the mix back into the squeeze bottle and then squirt it into the black dot vial again.

Since I have rarely any trouble over the summer, I'm likely to stick with what works for me. Sometimes high CYA/High FC running is necessary....ask aylad!...but running at 30-50 CYA has been effective for me. Poconos and I live much further north than aylad or PoolDoc, or even Watermom and pools do behave somewhat differently up here than they do in the South. Adaptability, though is key.

Carl