Test results on new pool in Tucson

[PoolDoc]

4 pucks per week equivalent to 1.5 lbs Cl2 gas
PF=6.7 for 18k gal pool

So 1.5 x 6.7 = 10 ppm chlorine per week.

Typical daily use, on a lightly used pool in a sunny area, when everything is running well is 1.5 - 2 ppm per day. 10 ppm is at the bottom end of that.

IF there is ANY algae, or ANY problems, chlorine use will be more on the order of 4 - 5 ppm per day OR HIGHER. Cleaning up algae can consume 100 ppm of chlorine in just a few days.

You need to MAINTAIN a chlorine level of 10 ppm (based on your CYA), doing what ever is required to get there. Once the pool is spic and span, you may find that 4 tabs per week (or 2 gallons of bleach) may be adequate to keep it there. But that's not the case, yet.

[Wilco]

Ok, that was what I was getting to, was the daily demand/loss do cl that could be expected. There was an algae bloom when we first moved in 6 weeks ago, but that cleared up with initial treatment. Water has gained clarity steadily, and looks great now, but maybe the residual of that bloom and the heat here increased the demand quite a bit. Are the hth shocks ( sodium hypochlorite) better for me with presumed high cya than dichlor?

[Watermom]

Check the label again. I don't think the HTH shock is sodium hypo. Maybe calcium hypo?

[Wilco]

Yep, calcium hypochlorite, you are correct.

[FormerBromineUser]

Oh my. You want a minimum 10 ppm FC (free chlorine) in your pool. You have Tri-Chlor pucks. They add FC but also add CYA and you don't want more CYA. You mentioned Di-Chlor, same thing. HTH shock adds FC but also adds calcium and your CH is high enough. You have used bleach (sodium hypochlorite), which will add FC but not affect CH or CYA. Is there any particular reason you prefer not to continue using bleach?

[Wilco]

At this point it seems that I will be pouring a gallon of bleach into my pool EVERY day. That doesn't seem feasible, but you are correct in exposing my faulty logic.

[FormerBromineUser]

Wilco, I hope you don't think I was hollering at you. I work with school kids and tend to "teach" in most things I do.

You just want to make your pool better and to use the BBB method; that's great! BUT it can be overwhelming at first. The time and energy it will take now to learn about pool chemistry will be greatly rewarded. You will become more than a pool owner; you will become a pool OPERATOR. The freedom and the sense of accomplishment, pride, and control you will gain is your gift from PoolDoc. Accept this gift.

Here is what I humbly suggest you do:
1) Conduct all testing below using ONLY your K2006
2) Add bleach to get your FC to at a minimum of 10ppm
3) Perform an overnight chlorine loss test. ASK if you don't know how to do this.
4) Report your results clearly on this thread
5) Do nothing other than maintain FC >=10ppm until you receive a response
6) Do not bring up any other side issues in the meantime.

Others who are more knowledgeable than I may disagree and if so, I hope they speak up, but I believe we need to get back to figuring out why you are not able to maintain your FC with reasonable quantities of bleach.