A Theory About Rising pH in SWG Pools

[Sentient]

My pool has three returns, the third does not bubble at all, I will leave it pointing up and point the other two down. I have a cover, which I keep on most of the time when the pool is not in use and need to add 1Qt of acid a week. It will be interesting to see if this makes any difference. I guess it is finally time to start a log so I can figure out what really is going on versus my gut feel.

Mark

[chem geek]

Mark,

That's REALLY interesting that one of your returns doesn't bubble at all. I assume all three are coming from the output of your SWG, right? You don't have any sort of bypass of flow with some going around your SWG to one return, right?

If the SWG output is going to all three returns, then is the one return with no visible bubbles at a farther distance away from your SWG? If so, then the theory of the chlorine bubbles needing more time to dissolve may very well be on the right track.

I would think that a pool cover would keep the chlorine in contact with the water longer so that it would eventually dissolve and not escape, but I suppose we'll find out.

I'm looking forward to the results of your experiment. Thanks!

Richard

[Sentient]

Yes, the first return is about 15 feet from the pool equipment, the second about 25 and the third about 40 feet away. My presumption has been that the bubbles all escaped at the earlier ports, but it could be absorption. I will ask some family members to also give the area where the bubbles surface a sniff to see if they can smell chlorine. Many of the tiny bubbles remain in suspension, never surfacing. I can wipe them off of any surface underwater with my hands, including the cleaner hose which is 20 feet from the nearest return.

There is no bypass of any kind. I have only a single speed pump and the flow rate is pretty substantial.

[fofa]

All my returns, 1 - do not bubble, at least that I can tell, 2 - are pointed down because my cleaner instructions said to do that. I still take 3 pints (30K gallon plaster inground) every week.

Just an F.Y.I.

[chem geek]

Thanks. This is just one of those areas with multiple factors. Lowering TA does help, but doesn't always help that much.

Not having any bubbles at all doesn't make that much sense since there should at least be hydrogen gas bubbles since I would expect the water to get close to fully saturated and for the hydrogen bubbles to outgas -- at least by the end of the day with the SWG still running. You might take a look at night with an interior pool light turned on (and, obviously, turning on the pump and SWG). Many times people don't see bubbles during the day, but can readily see them at night.

Richard

[fofa]

I'll have to keep thought in mind as I can't see squat right now thanks to Hurricane Ike and no power. If I ever get back in (running out of season now) I'll post back.