Can't lower PH in a green pool

[jrguzmanr]

I'm trying to open my green pool and my understanding is that I need to get PH into a recommended level but I can't get it down from 8.2. I've been testing with the TF test kit and located in NJ. These are my numbers:

FC 0 (have not added in chlorine as I'm looking to lower my PH first)
PH 8.2 (I've added 8 pounds if Clorox PH down and it still shows PH at 8.2)
TA 60
CYA 0

Am I doing something wrong? Any suggestions?

 

[PoolStored]

PH 8.2 (I've added 8 pounds if Clorox PH down and it still shows PH at 8.2)
TA 60
CYA 0

Am I doing something wrong? Any suggestions?

Let's switch to muriatic acid to reduce pH. Can you source muriatic acid? Better than dry acid as it adds sulfates.

Do you have pool math? Add enough muriatic to reduce pH by .4, pump running. Test 30 minutes later. Rinse and repeat until you hit your target.

 

[jrguzmanr]

I haven't gone to a pool store for chemicals in a loooong time, and it didn't occur to me to visit them for the acid until your post. I found it and will add some later today.

thanks!

 

[Lilypad]

Home Depot, Lowe's, Ace carry it too.

 

[jrguzmanr]

My local Homedepot and lowes did not have it in stock. Anyway, I've added 4 cups and it's still showing 8.2. I tested tap water and it's at 7.8 so I would think the testing is correct. Is there anything else I can do? I'm adding two cups at a time. I've had a pool for 10 years and never had an issue like this...I'm at a loss.

 

[Texas Splash]

I've added 4 cups and it's still showing 8.2.

Normally I would say continue the process. Post winter your pH may have been very high. Add a couple cups of MA to the water and let it mix for about 30 minutes then re-test and hit it again if needed. Before doing that though, please confirm .... how old is your R-0014 reagent? Since you have a TF-100, your are using R-0014 correct?

 

[Mdragger88]

What is your ta?
Do you have borates in the water?
You have a pretty good sized pool so 4 cups yields only about a .3 drop in ph each time.
Use
PoolMath to calculate amounts & aim for 7.6 - be certain of your MA strength. As pat said let the dose circulate about 30 minutes & check it again. If you wait too long to check it may rise again. Repeat until you’re in the 7’s then aim for 7.2.
& as mentioned, Verify your reagent is the correct one for your comparator & is not too old.

 

[jrguzmanr]

the agent is 2-3 years old. Since I tested it with tap water (7.8), I would think that shows that the agent is good.

 

[Mdragger88]

the agent is 2-3 years old. Since I tested it with tap water (7.8), I would think that shows that the agent is good.

2 years is the advertised shelf life (with proper storage) so it should be replaced to be on the safe side. You’ll probably need some fas/dpd replacements to get you through your slam if you haven’t replenished those so get all that on order now so you don’t run out.

 

[jrguzmanr]

I'm going to purchase new agents just to be on the safe side....thanks for the recommendation.

30 min to re-check? I would've thought that wasn't sufficient time to circulate. I will go ahead and do that.

 

[Texas Splash]

30 min to re-check? I would've thought that wasn't sufficient time to circulate. I will go ahead and do that.

Depends on your pool's circulation and pump speed. If you want to give it a bit longer that's fine too.

 

[nopain00]

I would recommend you try the Taylor acid demand test. In this test, you check your pH and then add the acid demand agent dropwise to your sample until the colorimetric test reads the target pH. There is a conversion included with the test so that you can convert the number of drops needed of the acid demand reagent to muriatic acid volume.

This process has a few benefits. One, it confirms that your pH test works. Two, it gives you an idea of how much acid you actually need. In cases where they may be a large buffer, the requirement may be high.

 

[jrguzmanr]

good news....after pouring in one gallon since yesterday it is down to 7.8!

Now the real work starts....SLAM!

thanks everyone!

 

[Newdude]

My local Homedepot and lowes did not have it in stock

Anywhere with a paint aisle (HD/Lowes/Ace) has it year round in that area. Paint stores as well.

Many have gone 'trade secret' on the strength with their MDSD listing 'between 10% and 34%' (or something like that).

Look for industry buzz words on the label if the strength isn't labeled. Green, eco or no/low fumes means it's half strength and you'll need twice as much.