New Sundance optima 880 owner and looking for some guidence.

retest ph after 10-15 minutes from your last acid addition & dose again to bring ph into the 7’s. If your ph is higher than the readable amount on the phenol red test just use 8.2 as your “current” & 7.6 as your “target” in PoolMath until you get a readable ph.
You are waiting too long to test again & the ph has risen back up. What takes days in a pool, as far as ph goes, takes minutes in a spa because of the aeration.
Each time you lower ph with acid you are lowering ta.
When your ta is very high the change can seem minimal but it is occurring. As the ta lowers you’ll notice the difference.
Test ta every 4 rounds or so to be sure you’re calculating the correct amounts of acid
So, I should focus on bringing down the PH first? My pool shop said to focus on the TA first.. Maybe that is my problem. I added 5oz of MA last night, woke up to a 7.8 PH, so I am making some progress.
 
So, I should focus on bringing down the PH first? My pool shop said to focus on the TA first.. Maybe that is my problem. I added 5oz of MA last night, woke up to a 7.8 PH, so I am making some progress.
Lowering ph lowers ta.
High ta isn’t hurting anything, just making ph rise more quickly. As ta falls the ph rise frequency will lessen.
You never want to lower ph below the 7’s.
Focusing soley on ta with acid additions can cause you to lower ph too low & lead to an acidic condition which is not good for your tub, its components, or bathers.
 
retest ph after 10-15 minutes from your last acid addition & dose again to bring ph into the 7’s. If your ph is higher than the readable amount on the phenol red test just use 8.2 as your “current” & 7.6 as your “target” in PoolMath until you get a readable ph.
You are waiting too long to test again & the ph has risen back up. What takes days in a pool, as far as ph goes, takes minutes in a spa because of the aeration.
Each time you lower ph with acid you are lowering ta.
When your ta is very high the change can seem minimal but it is occurring. As the ta lowers you’ll notice the difference.
Test ta every 4 rounds or so to be sure you’re calculating the correct amounts of acid
Okay. This seemed to be the ticket. Took 5 rounds at 2-3oz each time after running jets for 10-minutes. Per the test kit I'm at 7.6ph and 50-60TA. I plan to run the jets a bit more to see if PH creeps. What do I do if it does since I can't add more acid?
 
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Okay. This seemed to be the ticket. Took 5 rounds at 2-3oz each time after running jets for 10-minutes. Per the test kit I'm at 7.6ph and 50-60TA. I plan to run the jets a bit more to see if PH creeps. What do I do if it does since I can't add more acid?
Let ph ride when in the 7’s. When it rises to 8-8.2 lower to high 7’s with acid.
The smaller ph drops should have less noticeable impact on ta.
Be sure the water has been calm before testing ph.
If ta dips below 40 you may want to add baking soda to raise it back up to 50. Many people find a ta of 40/50 to keep things (ph) more stable in a spa - ymmv.
Be careful-go easy with additions,
you can always add more chems if needed but it is easy to overdo things in a small spa. With any luck you may find your ph quite stable at the higher end of the 7’s/8.0 with a ta of 50. Don’t rush to lower it.
I suspect as you replace water due to splashout & evaporation with your high ta water you will not often need any baking soda.
As @RDspaguy mentioned , lower your circ pump frequency and also be sure to be mindful of your water level- when too low the jets often cause more aeration
 
Let ph ride when in the 7’s. When it rises to 8-8.2 lower to high 7’s with acid.
The smaller ph drops should have less noticeable impact on ta.
Be sure the water has been calm before testing ph.
If ta dips below 40 you may want to add baking soda to raise it back up to 50. Many people find a ta of 40/50 to keep things (ph) more stable in a spa - ymmv.
Be careful-go easy with additions,
you can always add more chems if needed but it is easy to overdo things in a small spa. With any luck you may find your ph quite stable at the higher end of the 7’s/8.0 with a ta of 50. Don’t rush to lower it.
I suspect as you replace water due to splashout & evaporation with your high ta water you will not often need any baking soda.
As @RDspaguy mentioned , lower your circ pump frequency and also be sure to be mindful of your water level- when too low the jets often cause more aeration
Morning update: Checked PH first thing this morning and it was sitting at 7.7. I ran the jets and aeration for 20-30 minutes. Let the water settle and the PH was at 7.8 so minimal increase. I did another TA test to be sure. At 4 drops it is a very faint pink, 5 drops it is bright pink, 6 drops does not seem to make the color any darker. I think that tells me I am some place between 40-60TA?

This all seems pretty good, but just want to verify. Ordered the rest of my chemicals and plan to go away from the @ease system due to cost. Next focus is getting the CYA into range and start using bleach. Thank you @Mdragger88 for the advice so far!
 
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The end point of the test is when there is no further change so that sounds like your ta is 50.
With a ta of 50 my spa’s ph will hang in the high 7’s for a long time.
 
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So I should consider this balanced or should I try to bring it closer to 40 with a lower PH?
You’re golden right where u are 👍🏻
The ph will eventually rise - cuz that’s what hot tubs do- but just aim for no lower than mid to high 7’s once hitting 8.2 & the ta shouldn’t take too much of a hit.
Happy hot tubbing 🫧
 

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