Recent content by DougJack

This isn’t definitive, but I’ ve been able to get consistent CYA readings with the pool lab 2.0 using a pill crusher, then dropping the powder onto a folded piece of glossy photo print part and sliding it into the center compartment. CYA has been in the range of 15-60 and rational - meaning I...

I understand! I switched to the SWG and now I rarely if ever use it. Patio furniture is a good idea - and cleaning cutting boards.

I understand the whole concept now - thanks. Just for closure, I started down this path because I was having to use a lot more liquid chlorine than Pool Math suggested, not knowing that liquid chlorine has a pretty short shelf life. I just finished going through the measurement process with the...

You're right - I was looking at the ratio "between" -

Yep - you’re right. I trapped myself by thinking that FC was only active chlorine. Two questions that I have. One is what is the mechanism that lowers active chlorine as CYA ppm increases. Another is a practical one. I see the recommended FC/CYA ratio increases with an SWG. Is this still the...

So - I finally got it. I kept thinking that the DPD measurement was not measuring all FC + iso cyanurates. I see now that the measurement essentially removes the bonded HOCL and sees the FC as if the CYA wasn't there. So there is no need to make an adjustment in dosage to compensate for the CYA...

Hi, No I'm traveling right now, but I intend to run a test when I get home. I need to think through that test though.

Got it!

Thanks - I read through it. It made me appreciate some of the science and thought involved.

The rest looks like a gold mine.

That's great! on the first source it implies a loss of 12% in a typical hot tub per 24 hours.

I did know that, but didn't pursue it. Now I will

Thanks James

Great - it's going to be near the top of my list when I get back.

Sure - no one has explained the dynamics of adding FC. Simplistically if the Total bonded and unbonded chlorine is what is being measured, and I want to double the FC measured, and there is 20x more bonded than unbonded then I need to double the total. When I pour in the chlorine that pool math...