The Age Old Sanitizing Question

[waterboy5281]

I have read - ad nauseam - the countless posts detailing the advantages of liquid chlorine over stabilized chlorine and Ca-Hypo, and I just can't help but have some reservations.

I have inherited a 39K in-ground vinyl pool (no heater). I opened shop around 4 weeks ago, spent some time de-greening it with Ca-Hypo and I am happy to say it is crystal clear.

pH ~ 7.6

CYA ~ 30

CH ~ 250

TA ~ 100

I feel like my particular situation does not immediately lend itself to liquid chlorine. I'm in direct sunlight for the entire day - NO shade at all - and it eats up around 2ppm/day. I don't have a solar cover. So I'm expected to throw 2 jugs of bleach every few days? That just doesn't seem sustainable.

Judging by the empty Leslie's buckets in my shed, it seems like dichlor granules had been used. I remember seeing trichlor tablets in the skimmer during my youth. That's all the precedent I have to work with. I know for a fact my dad never used liquid bleach.

I've been searching for the *right* answer but I'm beginning to think it'll just take some trial and error.

I appreciate any help the forum can provide. I'm new here, so please do not hesitate to ask for any additional information.

[polyvue]

I have read - ad nauseam - the countless posts detailing the advantages of liquid chlorine over stabilized chlorine and Ca-Hypo, and I just can't help but have some reservations.

I have inherited a 39K in-ground vinyl pool (no heater). I opened shop around 4 weeks ago, spent some time de-greening it with Ca-Hypo and I am happy to say it is crystal clear.

pH ~ 7.6

CYA ~ 30

CH ~ 250

TA ~ 100

I feel like my particular situation does not immediately lend itself to liquid chlorine. I'm in direct sunlight for the entire day - NO shade at all - and it eats up around 2ppm/day. I don't have a solar cover. So I'm expected to throw 2 jugs of bleach every few days? That just doesn't seem sustainable.

Judging by the empty Leslie's buckets in my shed, it seems like dichlor granules had been used. I remember seeing trichlor tablets in the skimmer during my youth. That's all the precedent I have to work with. I know for a fact my dad never used liquid bleach.

I've been searching for the *right* answer but I'm beginning to think it'll just take some trial and error.

I appreciate any help the forum can provide. I'm new here, so please do not hesitate to ask for any additional information.

My perspective is that there is no such thing here as the "right" answer. If you're testing regularly, especially pH, Free Chlorine and CYA, and can maintain a minimum Free Chlorine level of 7 or 8% of CYA through the use of TriChlor or DiChlor... and don't mind draining some water from the pool on occasion when the CYA reachs intolerable levels (say over 70 or 80 PPM, when shocking becomes problematic due to an elevated need for chlorine) then you may be a candidate for using stabilized chlorine. This will be easier to achieve if you have a sand or DE filter (because backwashing removes water from the pool) and have a heavy bather load (more water loss due to splash out). If you use stabilized products exclusively you must understand that for every 10 PPM of chlorine (5 days in your pool?) added by these products, 6 - 9 PPM of cyanuric acid is also added to the pool. The chlorine gets used up, the CYA stays in the pool and doesn't dissipate through evaporation. So, with a current CYA level of ~30 PPM, how long might it take to reach 80 PPM? A month or two? So there's the issue.

[chem geek]

You could always be lucky and have water low in algae nutrients. However, clearing a pool of algae that is high in CYA level becomes much more challenging and keeping it clear becomes challenging as well unless the CYA is lowered.

The other option is to spend money on algaecides or phosphate remover products though most only inhibit algae but do not stop it completely. Some, like copper, certainly can prevent algae but can also stain surfaces and turn blond or gray hair greenish. Your pool is rather large so anything you do is going to cost you more because of that.

If you want to reduce your chlorine usage, you should seriously considering getting an at least partially opaque pool cover. As for dosing with chlorinating liquid or bleach, there are automated dosing options such as The Liquidator, a peristaltic pump, or a saltwater chlorine generator (SWG/SWCG) system.