Very high pressure with my DE filter

Here are my numbers what do I need to do now to get my FC to 5.5 AND PH down?
I just added 3/4 gal of 6% liq chlorine, 2.5 cups of 20 Baume Muriatctic Acid (all I have left on hand) 6 lbs calcium chloride and I have my chlorinator wide open filled with Cal-Hypo tabs 70.2% (bought last spring when my CYA was high).
FC 3.5
CC 1.5
TC 5
CH 250
TA 140
CYA 2
PH 7.8
 
Add liquid chlorine to raise your FC.

Your pH is fine. When it gets to 8, use muriatic acid to lower to 7.6 or so.
 

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Oh I added Pool Math to my phone weeks ago, I'm not sure Pool Math is helping me. So yesterday my FC was at 3.5, CYA under 20 (the pool store measured it to be 2), pH 7.8 and TA 100. Pool Math app said I needed to add approx. 3/4 gal 6% liquid chlorine to get to my target FC of 5.5. I added whatever it said and a couple cups more and my FC is 0 this morning! So, if you say that's because your CYA is low, well Pool Math knew that and should have had me add more Cl because now I've slid backwards considerably on Cl. How was that to get me to my target of 5.5? (My CC/TC is 2.)
I'm very discouraged by this. Pool Math also said I needed 10 pounds of dry stabilizer. I added 4 lbs yesterday with no measurable change today in CYA. I picked up another 4 lb bag today, I should have bought 2.
So now to get to 5.5 FC , Pool Math says I need to add 6 gals LC. I just added 6 gals the night before yesterday and about 1.5 yesterday. Boy, this is a very starnge season so far and expensive. Also, this whole time I have 3" Cal-Hypo pucks in the chlorinator with it wide open which seems to be doing nothing.
Why did FC go backwards so much overnight?
 
Without stabilizer, your FC will be consumed quickly in the sun. An overnight loss is likely because you have algae brewing.

You should add a enough CYA to get you to 30. "Enough" should include what you already added. If the recommendation to get to 30 was 10lbs, you should add 10lbs total, including what you already added.

CYA can take up to 24-48 hours to register on the test.

Pool math is a simple calculator. If your CYA is 0, it would tell you how much to add to get to your target FC. It knows nothing about your FC demand to make a recommendation to add more. Pool math is a tool and it takes the operator (you) to understand how to use it.

To determine if you have algae (even if you can't see it), do this test tonight. Link-->Overnight Chlorine Loss Test

If you fail, start the SLAM process to clear the pool. Link-->SLAM Process

If you pass, maintain FC in range for your new CYA of 30. Link-->FC/CYA Levels
 
I entered my CYA as 2 yesterday and my FC as 3.5 and my target FC as 5.5 and Pool Math claculated how much LCl to add, I don't remember the exact oz but it was less than a gal. I actually added more than a gal and today FC is 0.

Does TFP advise to add dry stabilizer through the skimmer as the directions on the bottle say? Just checking because I know some techniques or products from the pool store TFP advises differently.
 
Put the CYA in a sock. Tie the sock off. Hang it, carrot on a stick style in front of a return, at least 6" from the side of the pool. After about 1/2 hour it will soften and you can squeeze it a bunch to get it dissolved.

You may need to do multiple rounds as you can't get 4lbs in a sock...

If you are up for it, there is another thread on the topic...
 
That link was awesome, I'm going to do the laundry bag method, glad I asked!

Ok, I just read through the SLAM process again for the 10th time at least this week. Haha. So, I should not start the SLAM process today, I should wait until this stabilizer takes effect and I get up to 30 CYA even though everyday I wait the algae grows?

The reason I am wanting to start SLAM now without doing the OCLT is because I just read that if CC is over .5 you should start SLAM and mine is 2 even though my FC is 0. So start today or wait a day possible 2 for CYA to get up to 30? I'm so confused what to do now. The Cl appaers to just be eaten up quickly by the bright sunshine we're having and maybe algae. Do I put 5 jugs in now knowing it will burn right up or wait another day to see if yesterday's and today's stabilizer changes things. But then no Cl means the algea gets to have a party in my pool again today.
 
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Ya know, I have to say the pool looks so much better than yesterday which is confusing too. Yesterday, was mostly sparkling clear and blue except for the deep end which had a very slight greenish hint to the clear blue and there was a big limey-green stain on the deep end floor. Today, it is all sparkly blue and the big green floor stain is gone! We brushed and vacuumed twice yesterday and did both once again this morning.

Ok, laundry bag is in the pool. thanks. To use the calculator for SLAM, do I set my CYA at 30 or 0?
 
I know this is a lot of questions but I'm a first timer with the kit and the TFP system and I REALLY appreciate the help!
Can I attach a 17 second video to ask you if you would you say the black dot does or does not disappear in my CYA test? Looks like I can't. Here's a screenshot from the video of the moment it sort of does disapppear but then you see it a nano second later. Is this what I'm looking for? Screenshot 2024-07-08 at 1.58.58 PM.png
 

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