Recent content by nunk

Well I thought that I would provide an update. No testing or deliberate.additions have been made to the pool since my last post 5 weeks ago, but we have had 125mm of rain in that time. The SWCG has been adjusted to a lower setting (20% on the gauge). Today I took pool water samples to two...

To track the pH rise in the pool water, I just wish I had some m-cresol purple indicator (pH range 7.4 - 9.0) or thymol blue (8.0 - 9.6). The phenol red in the test kit has a range of only 6.4 - 8.2. The water currently tests at over 8.2.

This all started with a beautiful green pool which had developed over winter due to complete neglect. Also, unbeknownst to anyone, the Maltese Terrier had been excavating under the concrete slab on which were positioned the sand filter and pump. The slab eventually collapsed (the dog wasn't...

Update. Well a week has gone by and no testing, adjustments or maintenance have occurred. The SWCG is still merrily generating chlorine. A section of the bottom of the originally blue vinyl liner has turned white and there is a small area of crazing. The baskets in the skimmer box and...

Thanks for pointing me to the other posts and chart. That has nicely filled the gaps in my knowledge. As to your comment: "As for chloride ions not being consumed, it has nothing to do with whether you consider it HCl or NaCl. Chloride ions are converted to chlorine gas which dissolved in...

Thanks chem geek. Perhaps I should have also added: TA 120 ppm; and NaCl 3500 ppm. Could you possibly expand on the statement "The level of pH rise from carbon dioxide". I would have thought that carbon dioxide outgassing would occur at acid pH's where its in equilibrium with bicarbonate ion...

Thanks. Yes, my neighbour works on the 'set and forget' principle. Preventive maintenance? What's that? However, I was really wondering whether the pH will continue to rise? The SWG is a self-cleaning type so maybe the electrodes won't readily become scaled. But with the depleted hydrogen...

What is the likely water chemistry outcome for a vinyl SWG pool to which NO corrective HCl additions are made? The water is currently pH 8.2+, the FC is 10+ and the CYA is c.200ppm. The brand new SWG's certainly working well! This represents my neighbour's pool (no regular testing) and I'm just...

Thank you all for pointing out the misleading nature of that paper. And thanks especially chem geek for directing me to the links. I'm new to this forum. I don't have a pool but each of my neighbours have SWG outdoor pools and I have taken a bit of an interest in them, which is growing as I...

I came across this 1997 paper entitled Cyanurics - Benefactor or Bomb? by Kent Williams (attached) I'm wondering if this paper has previously been critiqued by our experts and what might it's relevance be in the light of current knowledge on the subject?