High PH. low TA, which way to go first?

[mepot101]

Todays numbers:
FC2.5
CC0.0
TA70
CH200
CYA30
CSI-0.05

So my ph is up, so I need to add some muriatic acid, but that will bring my TA down? PM calls for 38oz baking soda to bring the ta up, 16oz ma, to bring the ph down.
Which way to go first???

Also, my cya is probably less than 30, ok to use some dichlor pucks to add a small amount of cya?
Looks like 2 pucks will bring my cya up 3.8,

Thanks,
Mike

 

[frogabog]

Your FC is low. If you think you're at 26-27 CYA, we will call that 30 and you should chlorinate for 30 CYA. 3ppm FC is your minimum, 7ppm is your target. Add enough chlorine right away to reach 7ppm (if not 8ppm).

Your TA is fine right where it is. Don't mess with it right now. What is the pH?

 

[mepot101]

OOPS. ph is 7.8. The chlorine level is about where it is daily at test time.
Added 31oz today, seems to have settled around there most days.

 

[Msch99]

Yes adding MA will lower PH and TA.

Is you PH rising rapidly? It may be that 7.8 or so is where it likes to be.
I am not an expert but if it stays between 7.8 and 8 for an extended period, I wouldn't get too excited until it gets closer to 8, then maybe only lower to 7.6 or so if your pool likes the higher range.

Lowering PH to 7.2 looks like it would take 29 oz. of MA which would also lower TA by about 7.

 

[frogabog]

I am going to suggest that you aim for your target at night (which is 7ppm) and hopefully you shouldn't fall below 3 by the time you test and add again the next evening.

Falling below minimum, even if your pool likes to do that every day, is asking for problems. Your pool is not a precocious toddler that gets it's way. You tell it what you want it to do, and it does it. Else you spank it with more chlorine.

I like to aim for 1ppm over target, personally. It allows me to never fall below minimum, but occasionally I do get within .5ppm. Also, if you have swimmers, you'll need to adjust your FC accordingly (i.e. more chlorine than just target and minimum).

 

[frogabog]

Another note, if you'd like to lower your pH some and raise your CYA you can use those pucks. They do exactly that, and your TA will not be affected.

Just make sure to use Pool Math to sort out how much your pH will be lowered in relation to how much FC is added vs CYA rise. Figure, per 1ppm FC about .9ppm CYA rise. I don't know the pH off the top of my head but Pool Math does.

 

[mepot101]

Per PM, my cl target is 2.0 to 6, added 31oz today. Also, my ph does seem to like to stay around 7.6, usually settles for a few days at 7.8, then I add some ma to keep it from getting out of range.

Also, does my pool math logs show up, I don't see them on my screen?

 

[Msch99]

Yes your logs show. I clicked on your profile and they were there.

 

[mepot101]

Looks like 2 8oz pucks will raise my cya 3.8, and lower ph by 0.2. They seem to take about a week to dissolve in the floater, seems like it won't make too much difference over an extended time.

 

[frogabog]

Oops, ok... my mind was in my 3-7ppm mode for 30 CYA so you're right. 2ppm is your minimum. I still like to think 3-7 when I'm at 30 so, sorry.

Your pool math logs do show up. Hover over your screen name to the left of one of your posts, you'll see the blue button.

 

[mepot101]

And thanks for the help, since joining the site my pool looks better than ever.

 

[Msch99]

You can add to your signature too I think, if you wish.

 

[frogabog]

I put two pucks into my skimmer, ran the pump 24/7 for about 4 days. My CYA rose by 10ppm and pH dropped from 8.2 to 7.3. My FC remained around 5ppm those days.

Pucks came out as soon as I got the results I wanted. Didn't take long. I have about 3800 gallons.