What to change?

[hwade]

Long time lurker, first time poster. I'm new to the BBB method so I could use some advice on what to adjust. I've got a 13,500 gallon pebble pool with a SWG. As of this evening my numbers are:

FC: 3.5
CC: 0
pH: 7.5
TA: 80
CH: 270
CYA: 50
Temp: 70
Salt: 3450
Borates: 50

This gives me a CSI of -0.5 per the pool calculater.

My plan was to bring pH up to 7.6, CH up to 300, and CYA up to 70. This will still result in a CSI of -0.42. Beyond this, what should I adjust to bring CSI closer to 0? I've played around with the numbers in the calculator and it appears the only way to get CSI below -0.30 is to take at least one of the other parameters out of the recommended range.

Thanks!

 

[PaulR]

Is your pH stable, or does it tend to go up a lot? If it's stable, you could try raising TA a little.
Other than that, keeping the pH a little higher seems like the best approach.
(Boy it feels weird to recommend a higher pH...)
--paulr

 

[Richard320]

Have you tried plugging in different temperatures? Things will change when it heats up in the summer.

 

[hwade]

Thanks for the input! pH is relatively stable. At my current levels the temp would have to hit 93 to get CSI under -0.3. If I make the changes I mentioned above I would need a temp of 84. Should I ignore CSI for now and wait for warmer weather?

 

[baudilus]

How does the water look?

 

[hwade]

The water looks and feels great. It's crystal clear with no hint of problems. The kids have already been swimming twice this week.

 

[JasonLion]

You actually want the CSI to be a little negative, not at exactly zero. Almost all of the natural variation in the levels is towards higher CSI levels. You need some "head room" to allow for unpredictable occurrences. For example, PH almost always goes up over time, especially with a SWG. CSI is also significantly higher inside the SWG cell.

I would raise CH up to around 300 to 320, and CYA to between 70 and 80 and leave everything else alone. The PH will drift up on it's own eventually.

 

[hwade]

This will be our first summer with a pool. I'm trying to learn as much as possible as quickly as possible so the input is greatly appreciated.

I remember reading in another thread that as you add water to offset evaporation your CH will go up. I'm in Texas so I'm anticipating a fair amount of evaporation in June, July, and August. If I want CH to be at 300-320 should I try to get there now or let it naturally happen over time as I add water?

 

[PaulR]

What's the CH of your fill water? How fast the pool's CH goes up will partly depend on what you're replacing the evaporation with.
--paulr

 

[JasonLion]

Measure your fill water CH level to see if this will be an issue for you. In much of Texas there won't be any issues. High CH level problems are much more common in places like Arizona and Nevada, though they can happen in some parts of Texas.

 

[hwade]

I'll measure the fill water tonight. Thanks so much, guys. This site is awesome!