what order to add the chemicals

[BigDave]

At pH 7.5, I don't see why you'd raise it, that's perfect for most. Your SWCG should tend to push pH up but the relatively low TA should reduce pH rise. Sounds to me like you're in a pretty good place - you've already addressed the CYA and FC issues.

[PoolDoc]

Alison,

I'd really, really encourage you to abandon the idea of an "ideal" or "perfect" order of things. We've found that, when people pursue pool perfection they almost always end with over-testing or over-treating their pools. What you want is 'good enough', not perfect.

The whole idea of a "perfect way to operate your pool" assumes that we know far more about pools and water chemistry then we actually do! If your water is clear and comfortable, and not damaging your pool, or costing too much time or money . . . that's optimal!

[alisonquilts]

I'd really, really encourage you to abandon the idea of an "ideal" or "perfect" order of things. We've found that, when people pursue pool perfection they almost always end with over-testing or over-treating their pools. What you want is 'good enough', not perfect.

I appreciate that, PoolDoc, and it is certainly the approach I generally take in life! The only reason I am so curious is that I am sure I read a thread which mentioned a couple of chemicals that would precipitate if you added them too close together (but I can't remember which ones), and I also thought I read a thread which suggested that it is important to get your (pH/cya/TA) in the right ballpark before adjusting your (pH/cya/TA) because of the way they interact. I just can't remember the threads accurately!

It isn't perfection driving my question, it's memory impairment!

Alison

PS And since I have started following the advice of this forum, and testing my own water, I have become a much more serene and confident pool owner, and my pool has been much more stable. Thank you!

[aylad]

You don't want to test or adjust pH if your chlorine is high, because the pH test results will be falsely high. So if you need to adjust pH, do it before you shock the pool. Also, if you have a high calcium level, adding cal-hypo or baking soda/alk up can cause cloudy/milky water problems. Other than that, everything else should work out okay...

[alisonquilts]

Great! That is exactly what I wanted to know. Thanks!

Alison

[TheKs]

Aylad,

You said: "You don't want to test or adjust pH if your chlorine is high, because the pH test results will be falsely high. "

What level is considered "high" for the chlorine?

Peggy

[Charlie_R]

In my own small pool, I've noted that the pH false readings seem to start for me at around 30 - 35ppm FC. I don't know if it would be true for a larger pool, though. Another thing I've noted is when the FC is high, the pH test tends to climb the scale over time. The higher the FC, the faster the climb. At 50 FC, it is a noticeable color change. Like within seconds, the color will change from 7.2 all the way to above 8.0. Where at 30 FC, the change creeps up on you, taking 2-3 min to go from 7.4 to 7.6.

As I said, this appears to be true for a ~4.4k gal pool, but as I have nothing to compare it to, I don't know about larger or smaller pools.

[PoolDoc]

The only reason I am so curious is that I am sure I read a thread which mentioned a couple of chemicals that would precipitate if you added them too close together

That's when you add calcium PLUS either sodium bicarbonate (Alk Increaser) or sodium carbonate (pH Increaser) at the same time. You have a vinyl pool, so you NEVER need to add calcium. (Problem solved!)