Questions about bestway agp sizing

So I added a liter of muriatic acid yesterday and when I tested just now, it looked like it was going to be 7, but it turned purple really quick. Any suggestions? Was reading that this maybe caused by high chlorine levels and ijust added chlorine so I'm thinking I should add some soda to increase the ph. Am I on the right track? Looks like TA is 80-90
 
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Are you testing PH immediately after pulling sample? Don't let the sample sit. Also, try using 4 drops of reagent instead of 5.

Please test again and take a photo of result. Are you holding it up to a white wall? I usually hold mine up to kitchen window, so it is well lit.

You want to test about 30 min after your MA addition. Check your return and make sure the water coming back into the pool isn’t creating splash. Lastly, did you ever PH test your fill water, right from the source?
 
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Just tested the water source and tested the pool again, does not appear to be changing to purple after 3 mins so far unlike last time. Here is both the water source and pool water photos against a white bucket.
 

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Why are you waiting 3 minutes? When you pull the sample, do the drops, check the color, and call it a day. With that second photo (pool water) you now have low PH. Your fill water is fine, so that isn’t driving your PH up.

What is your current TA?
 
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Why are you waiting 3 minutes? When you pull the sample, do the drops, check the color, and call it a day. With that second photo (pool water) you now have low PH. Your fill water is fine, so that isn’t driving your PH up.

What is your current TA?
I'm not waiting, I did the test immediately, my comment about 3mins was time that I counted to see if it was going to turn purple like last time. TA is 80-90.

If my ph is say 7, I need to add about 3lbs of mule 20 correct?
 
I'm not waiting, I did the test immediately, my comment about 3mins was time that I counted to see if it was going to turn purple like last time. TA is 80-90.
What I’m saying is that it doesn’t matter what happens 3, 5 or 10 minutes after you add reagent. Your PH result is what you see immediately after adding reagent.

Ok, I would leave your PH alone for now. Test again over next couple of days to see how it rises. Please keep us posted!
 
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What I’m saying is that it doesn’t matter what happens 3, 5 or 10 minutes after you add reagent. Your PH result is what you see immediately after adding reagent.

Ok, I would leave your PH alone for now. Test again over next couple of days to see how it rises. Please keep us posted!
Thank you so much! This stuff is quite the learning curve 😂.
 
no don't add anything. don't forget chlorine over 10 makes pH inaccurate. and to raise pH just aerate your water, you don't need to add anything, especially stuff that may also raise your TA. turn your return eyeball up so it agitates the surface or send a bunch of kids in to splash around.
 
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So, just got back from 10 days away. Things with pool had been well. Water is turning a slight green and cloudy when I got back so I ran some tests. Here are my numbers. I did vacuum to collect as much as possible but there does not seem to be a lot of suction. I have two outlets and I've blocked one of them when I use the vacuum. I'm wondering if I should do a backwash and rinse of the sand filter or add more chlorine because I'm lost. It's pouring out today, don't know if that will make it worse. I'll try my best to get a pic later when the rain decides to clam.

cya - 50
fc - 7
ph - 7.4
ta - 80-90
 

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Ok wow. I wonder why this happened. Wife said it was excellent only 5-6 days ago, blue and very nice swim. I guess the first thing I should do is ensure that the pump/filter is fully cleaned and get started. According to the chart, I need to bring my fc level up to 20!

Using the pool calculator, looking at using 113oz, so basically 3.5liters. Yikes! Going to have to run to the store anyways.
 
Ok wow. I wonder why this happened. Wife said it was excellent only 5-6 days ago, blue and very nice swim. I guess the first thing I should do is ensure that the pump/filter is fully cleaned and get started. According to the chart, I need to bring my fc level up to 20!

Using the pool calculator, looking at using 113oz, so basically 3.5liters. Yikes! Going to have to run to the store anyways.
Was someone adding liquid chlorine daily and/or testing while you were gone? 5-6 days is a long time if levels get low.
 
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Yes, I gave my wife in already poured cups and to add each one every two days. I just checked the filter and there seems to be very little flow, would that be the cause?
 
I just checked the filter and there seems to be very little flow, would that be the cause?
Being green you have algae. It will easily overrun the small filter no matter what you do. We always recommend going huge to get more time between cleanings but it’s counter productive In cases like yours to spend several times the cost of the pool on larger equipment.

So frequent cleanings will be needed but it will work.
 
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you should probably be adding chlorine every day until you really have a handle on what you are doing. you can get away with 2 or 3 day dosings but it is risky even for experienced people. too easy to lose enough chlorine to get down into danger/too low periods where algae get going. it isn't the filter causing the problem, that is another symptom - it is algae growing and clogging the filter. the problem is not enough testing and chlorine.
 
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Thanks for the feedback. Initially I was measuring how much chlorine I was losing per day and putting in enough to maintain 7-8 fc. I thought that I was doing it correctly, measure daily and than once very few days and up to 4-5 days. I must have miscalculated somewhere along the route. I just did do a backwash of the sand filter and I must admit that the flow is much better. I put in enough chlorine to bring it up to 20 and will test it again later. And in doing so I will continue to test and however when it is safe to say that this is done? Reading says losing 1 fc overnight and clear water; is that still the gold standard?

My pool was losing about 3 fc per day and there wasn't any issue until now when I noticed the pump not performing as it did. A complete coincidence perhaps.

Thanks again for the help folks.
 
I thought that I was doing it correctly, measure daily and than once very few days and up to 4-5 days. I must have miscalculated somewhere along the route.
4-5 days could have drastically different needs on those days. You fell short somewhere in the middle. Maybe it was particularly sunny ? You can usually guess today based on yesterday. Any longer than that starts playing with fire if you don’t know all the chemistry backwards/forwards *AND* be totally one with your pool.
And in doing so I will continue to test and however when it is safe to say that this is done? Reading says losing 1 fc overnight and clear water
Yes.

Clear water
FC overnight loss of 1 or less
.5 CC or less

*for the record I personally don’t want to pass on a technicality with a 1 FC loss. ‘Cs get degrees’ they say, but I want my pool to pass with Dean’s honors. It’s my own doing and being ‘extra’, but it is so much easier to hold a SLAM for an extra day or two to be absolutely sure than it is to quit early and have to start with the hard part again in a week or 3.
My pool was losing about 3 fc per day and there wasn't any issue until now when I noticed the pump not performing as it did.
Maybe the decreased flow caused some dead spots with poor circulation and the algae got a foothold ? Maybe you were in the verge of an algae bloom and some algae was enough to clog the filter and make you pay closer attention ? Coulda been a lot of things and we’ll never know. But we know what to *do* about it. We got you. :)
 
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So first off, you folk are amazing and correct.

Secondly, I was disappointed with the vacuum that I have on the last try (10 days ago) because it wasn't very good. Obviously it was the filter that needs to be cleaned that was causing the poor performance. So, basically it was my fault and not the actual vacuum or the chemicals. I just did a terrible job of keeping the pool cleaned putting blame elsewhere up instead of just lazy and inexperienced. I've been working on it for the last hour and it was amazing how green the bottom of the pool was. I'm colour impaired and I can tell the difference from one side compared to the other.

Since yesterday, I'm currently sitting at 15fc so I'll be dumping another 43oz to get back to 20. But it's pretty amazing how clearer the water is already.

Thanks again!

Note: it was the last 10 days of heat and full sun...
 
during a SLAM, test and add chlorine as often as you are able. if you are around it can be every hour at the beginning, but at least 2 or 3 times per day. you want to keep that chlorine level high enough most of the time to do the job, if you are only testing and dosing once per day you should over-dose it a bit so it stays at that SLAM level as much as possible.
 
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