3 weeks and no bottom in sight!

Puddleduck

Member
May 30, 2020
11
Whitesboro/NY
Hello everyone! Thanks for your help!
We bought our home last fall, the pool had not been opened all that year and didn’t have a cover. We put leaf cover on for over winter and when we opened it this spring- swamp water!
We followed the pool store recommendations as we started educating ourselves and ended up here. I have my TF-100 kit finally and am waiting for our dolphin to arrive tomorrow to help us out.

So- many questions:
Regarding testing- I have the smart stir, I kept is spinning as I added the drops. The alkalinity test turned pink at 140 but stopped changing more pink at 160, what is the value?
Why is the recommended level of alk in pool math 50-90 when the store says 125-150? Seems like a huge difference so I’m either way high or just right.

During the chlorine test the solution turned clear, but then as it sat for a few minutes while I read the instructions the solution started Turing pink again- does that mean I had to continue to add drops? Because in that case my FC is higher than 3.

Test results:
FC 3
CC 1
Alk 160
CYA 30
pH 7.5

We would like to change the sand in the filter and add DE to get things cleared as fast as possible. The plan is to do this today prior to starting the SLAM for optimal conditions.

So 1st step- lower pH to 7.2 : will follow pool math instructions on how much product to add.

Would it be a good idea to raise the CYA to 40/45? That would help protect the chlorine better right?

Next is pool math again to figure out how much chlorine to add to reach target chlorine levels based on the cya/FC chart.

Then test FC twice? daily to maintain shock levels.

Until it passes the overnight Cl loss test.

Then theoretically our water will be crystal clear, right?

Thanks for your help!
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Also, this is our filter- I don’t know how to describe it. We have been backwashing it when the pressure goes up. So it runs around 10 when clean and we backwash when it gets close to 15.
 

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hi... with the alkalinity test when i do it it goes kinda dull red, another drop makes it go bright pink, then another drop makes it go hot barbie pink!! then i add another drop and it doesnt change anymore so i know to count only till the drop that first drop made it hot barbie pink.

dont change sand- clean it

maddie....will answer more as i can later
 
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Why is the recommended level of alk in pool math 50-90 when the store says 125-150? Seems like a huge difference so I’m either way high or just right.
TFP is science based and does not stay in the "dark ages" aka the way it has always been done. We have a section called the Deep End. You can look for ChemGeek to read what he has written. That is where our levels are based on. We are always learning and adjust as needed if we find a better way.

During the chlorine test the solution turned clear, but then as it sat for a few minutes while I read the instructions the solution started Turing pink again- does that mean I had to continue to add drops? Because in that case my FC is higher than 3
Once the FC test turns to clear call it. If you allow it to sit it will turn pink. Just ignore it.

Would it be a good idea to raise the CYA to 40/45? That would help protect the chlorine better right?
Nope I would leave it at 30 as it uses less chlorine to get to SLAM level.

hen test FC twice? daily to maintain shock levels.
Try for at least 3 times a day. Now if you can do 4 or 5 a day that is even better. Two is the bare minimum for testing.

You are SO close already!!!
 
Ok, so water hasn’t changed much. We missed a day of slamming, but I did an overnight chlorine loss test knowing our levels had dipped down. So last night our chemistry was:
FC 5
Ca 100
Alk 150
CYA 30
PH 7.2
This am FC was 4.5

We did a deep clean of the sand, added DE, have our Dolphin in there couple times a day, have the filter going 24hrs. We’ve seen some sand in the pool and the vacuum keeps pulling out sand not really any leaf debris.
So not sure where to go from here... do we need to empty our filter and check the laterals? Some people swear by baking soda (but our alkalinity is already so high), hubby wanted to try a water clarifier- that didnt do anything.

How do we get the alkalinity down? We raised the chlorine and its evaporating off but it hasn’t changed much.

Thanks for Your help!
 
For a CYA of 30, your SLAM level is 12. Try to keep your FC at 12 and that should help speed things along.

I'll let others comment on the sand filter, but I do know that is the slowest type to filter out particles so you will need some extra patience here. Also, I believe it is DE, not baking soda, that people can add to their sand filters to help them along. Even if you have something going on with your filter, chlorine should be your #1 priority in a SLAM.
 
Ok, so water hasn’t changed much. We missed a day of slamming, but I did an overnight chlorine loss test knowing our levels had dipped down. So last night our chemistry was:
FC 5
Ca 100
Alk 150
CYA 30
PH 7.2
This am FC was 4.5
FC needs to be maintained at the higher SLAM level for your CYA/30 --> FC/CYA Levels. Test and up FC as often as you can.

We did a deep clean of the sand, added DE, have our Dolphin in there couple times a day, have the filter going 24hrs. We’ve seen some sand in the pool and the vacuum keeps pulling out sand not really any leaf debris.
So not sure where to go from here... do we need to empty our filter and check the laterals? Some people swear by baking soda (but our alkalinity is already so high), hubby wanted to try a water clarifier- that didnt do anything.
When you deep cleaned it, could it possibly have unseated the laterals? If you are finding actual sand, you may need to get a tarp and dump the sand filter to reseat everything and make sure no sand is where it "shouldn't be"

How do we get the alkalinity down? We raised the chlorine and its evaporating off but it hasn’t changed much.
No need to "focus" on a set TA (otherwise it will just be a yo-yo of up & down, up & down)
 
We were maintaining the chlorine levels at 11/12 other than the past 48 hrs. I don’t understand how the extra chlorine will help clear the water. My understanding is that if my overnight test is fine that means I don’t have any organic debris eating it up - so I should be able to go down to maintenance levels.
Is there some other clearing action the chlorine has?

Some people swear by dumping 3-5 pounds of baking soda into the pool and it “clears overnight” not into the filter. 🤨

Also since washing the sand and adding DE our filter pressure keeps creeping up from 10 to 15 in about 24 hrs, so I have to keep backwashing it and refilling the DE. Yesterday I only added a 1/2 cup! I guess that means it’s working though?

Thanks for helping understand all this 😁
 
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The 3 criteria to ending a SLAM are:
  • CC is 0.5 or lower
  • You pass an OCLT
  • The water is clear
I dont see CC listed in your test results, but it sounds like your water is still not clear, so keep slamming away. Keep in mind that the cloudiness you see can be a mix of dead and alive algae. By dropping your FC down to maintenance, I worry you may give that still alive algae a chance to reproduce and return, erasing 3 weeks of hard work.

I dont understand how the baking soda would help "clear things up" and certainly is not anything I have heard reported on here. Sounds like a Facebook, friend of a friend type of a rumor. Since your TA is already very high, I would avoid this since Baking Soda is legitimately used in pools to raise TA.

You got it right on the DE in your filter. It grabs the smaller particles, but also clogs up quicker and requires frequent backwashing.

Here would be my suggested steps:
1. Vacuum to waste all of that gunk at the bottom of your pool. Continue doing this if more gunk appears.
2. Raise your FC to SLAM levels and keep it there until you are completely done
3. Continue to backwash your filter. If you have time to add DE everytime and backwash, that will help speed the process along but can also be tedious. If you dont feel like that, save the DE for the last few days of your SLAM and/or when you have the time (like a weekend) to babysit the pool and backwash extra.
 
WE DID IT!!
Ok, Finally got the water clear, it was great the last 5 days where we could actually see a difference every day in how clear the water was until we finally shouted for joy the first time we saw the deep end drain!
We ended up changing the sand even though we cleaned it out, now we can maintain it with deep cleanings before closing.
So now a couple questions-
yesterday our FC was 16- stable overnight so we didn't add any chlorine all day yesterday. This evening's labs:
FC 10.5
CC 0
Ca 100
TA 140
CYA 40
pH 7.5

So even though the FC is on the high end it's still safe to swim in, correct?

From here forward can I use the taylor kit for chlorine and pH once my levels drop to around 5 to maintain the chlorine levels?
Is it common to need to add chlorine everyday? We have liquid pool chlorine we're using during the SLAM- do we change to tablets now?

Thank you!
 

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Print these out:
Pool School - Basic Pool Care Schedule
Pool School - Recommended Levels

Bookmark these:
Pool School - Recommended Pool Chemicals
Trouble Free Pool
Pool School - ABCs of Pool Water Chemistry

Here is THE chart to help you know it is very safe for you to swim. So long as your FC is just below the SLAM level for your CYA you can swim! FC/CYA Levels

If you do use any tablets know they add CYA and too much CYA is not a good thing. The more CYA you have the more chlorine (FC) you will need to keep your pool clear. I only use tablets when I go on weekend trips and such. Other than that I use liquid chlorine.

Kim:kim:
 
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You have done so well that you need to move those pics where they belong

Great job
 
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