I need advice on what to "attack" first ...

Debra Joan

Bronze Supporter
Jun 18, 2020
95
Peachtree Corners, Georgia
The cover has been removed and I'm looking at a green lagoon.
I've skimmed everything off the top and picked up what I can from the bottom.
I've cleaned the sand in the filter.

I've been to "store" and picked up 12 glns of chlorinating liquid made 22035 (newest I could find).

I feel like I'm starting from scratch testing the water but here's what I've got:

chlorine <1
pH 8.7
TA 50
CYA 20

I know I need to lower the pH for my "cl" to work .... what do I use to do that?
Do I need to raise CYA before I lower pH and what's best to use to raise CYA?
And I need to raise TA but do I do that first or last?

What order should I do these things to start SLAM?

(what I learned last year is coming back to me slowly .... I'm thankful for the help!)

DJ
 
I know I need to lower the pH for my "cl" to work .... what do I use to do that?
You should use Muriatic Acid. Use PoolMath to calculate how much to use
Do I need to raise CYA before I lower pH and what's best to use to raise CYA?
Are you sure your CYA is 20? Does the dot disappear when you glance at it and the CYA is at the 20 mark?
And I need to raise TA but do I do that first or last?
You should use some baking soda to bring the TA up. Can be done slightly before or after the MA (our most people definition of at the same time). Again use PoolMath to calculate how much to use.

Hint for next year: If you open before water temp goes above 60F you have a bigger chance of opening to a crystal clear pool.
 
I just tested:

0 chlorine
I won't do anything about this until I get TA and CYA adjusted.

TA 40
For the low TA I've added 140 oz. (by volume) of baking soda. That's all I had in hand. The chart shows 195 oz. to get me to 80.
I'll test again and readjust before adding more baking soda when I return from the store.

pH - chart shows 29 oz. of muriatic acid. Should I add 1/2 that first and retest or just add the 29 oz.?

CYA 20
The dot was still quite visible, waist high, after slowly adding the entire red capped bottle of pool water and R-0013. It was mixed, I waited 30+ seconds, another mix and then in to CYA VIEW TUBE. The chart shows 35 oz. granular or 90 oz. liquid stabilizer. Is one preferred over the other, granular vs liquid?

From last year's mistakes, or I should say lessons, I might be giving too much information and apologize in advance. Two major items were pump speed and using the everyday chart instead of the SLAM chart. For speed I was running at the maximum 3450. I was told the filter worked better at lower speeds. To adjust the water, as far as TA and CYA and pH, what speed should I set my pump? For the moment I'm on recirculate, 2500. This is just to mix the baking soda while I go get the muriatic acid and stabilizer.
 
Stop with the baking soda. TA is the last thing to worry about. It may come down a little with your acid , but even 50 is fine. I always keep mine in the 50-60 range

With the "lagoon", is the water circulating? If yes, add half the acid and circulate for 30 - 60 minutes. Test and add more to get to 7.2

Liquid and granular are the same thing, but liquid is a lot more expensive. I'd use granular, pour the amount you need to get to CYA 30 (from 20) in an old sock and tie the end. Suspend it in the water or put it in a skimmer if it doesn't block all the flow. Squeeze it every 10 15 minutes and it will dissolve quickly. I wouldn't even retest, just assume 30 and start your SLAM


 
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Honestly, I would wait to raise CYA until you have finished the SLAM. Raising CYA will raise your chlorine level needed to do the SLAM and cost you more chlorine.
I'd do the SLAM to get free of algae & then raise CYA to final target.
Worry about TA last.
Keep on top of pH and FC, CC & get it clean. Then bring everything else in line. It will save you money.

If your CYA was 0, then yes, you should get it to 20 or 30. But if you are at 20 now, then I'd not worry about it & just stay on top of the chlorine & pH until done cleaning up.
 
I'm very sorry and have been caught up again with my poor description.
The dot is quite clearly visible when I've added all the mixture so my CYA is actually below 20.
How do you accurate CYA below 20?
I've no idea how much below 20 so I've added stabilizer using 20 in the pool calculator and will recheck in 24 hours.
I'm running the pump constantly on recirculate at 3450. Can anyone share opinion(s) on pump speed.

Thank you all for advice
 
I'm very sorry and have been caught up again with my poor description.
The dot is quite clearly visible when I've added all the mixture so my CYA is actually below 20.
How do you accurate CYA below 20?
I've no idea how much below 20 so I've added stabilizer using 20 in the pool calculator and will recheck in 24 hours.
I'm running the pump constantly on recirculate at 3450. Can anyone share opinion(s) on pump speed.

Thank you all for advice
You cannot measure CYA below 20. Add to 20 and retest, then add 10 more, retest, add 10 more retest until you get to your target.

No need to crank-up the RPMs too much. Your chemistry and the correct FC "maintained" is what you need. Continue to run the pump 24/7. Low is fine (1200-1800), and occasionally bump-up to purge air or assist with vacuuming as needed. Backwash when filter pressure increases by 25% and maintain the FC as best as you can until you pass all 3 SLAM criteria.
 

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Just keep in mind - it's a process, not a one-time bump of your FC. You have to test often and bring the FC levels back to the elevated level each time. The idea is to maintain the high FC level so we know everything is dead.
 
Update and questions.

Tested this morning before treatment:
TC 7
pH 7.5
TA 80
CYA 20

The pool has gone from dark green to almost a Gatorade green. The pump has been running non stop at 2500.
The filter gauge has increased slightly .... from 10 to maybe 12. It does drop to 0 when pump is off.
One of last year's mistakes, or I should say lessons, was running the pump at full speed during SLAM, 3450.
The filter shot up 15 lbs. every few hours and had to be backwashed. Now I'm concerned the filter isn't "catching"
the dead algae. Is it normal, after 5 days of SLAM, for filter pressure to increase so little?

I'm happy with the color change and see less debris each time I sweep.

Next ... using the chart to calculate amount of liquid chlorine to add to get my SLAM target of 10 the chart shows:
Add ______________ oz. 6 weight % bleech

I'm using Pool Essentials Chlorinating Liquid with Sodium Hypochlorite 10%
Should I be changing the "6" to 10?

Thanks team TFP
 
Update and questions.

Tested this morning before treatment:
TC 7
pH 7.5
TA 80
CYA 20

The pool has gone from dark green to almost a Gatorade green. The pump has been running non stop at 2500.
The filter gauge has increased slightly .... from 10 to maybe 12. It does drop to 0 when pump is off.
One of last year's mistakes, or I should say lessons, was running the pump at full speed during SLAM, 3450.
The filter shot up 15 lbs. every few hours and had to be backwashed. Now I'm concerned the filter isn't "catching"
the dead algae. Is it normal, after 5 days of SLAM, for filter pressure to increase so little?

Backwash when you go up by 25% - if you start at 10 and are going to 12, then that's almost time to backwash.

You'll catch more as it goes to a milky blue. Still, you can try running at higher RPM to see if you can get it to catch more. I don't know that there's standard advice as to filtering quicker or slower to go faster and catch more of it.

I'm happy with the color change and see less debris each time I sweep.

Next ... using the chart to calculate amount of liquid chlorine to add to get my SLAM target of 10 the chart shows:
Add ______________ oz. 6 weight % bleech

I'm using Pool Essentials Chlorinating Liquid with Sodium Hypochlorite 10%
Should I be changing the "6" to 10?

Thanks team TFP

That's correct - change the percentage to 10% to calculate for 10% LC.
 
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Backwash when you go up by 25% - if you start at 10 and are going to 12, then that's almost time to backwash.

You'll catch more as it goes to a milky blue. Still, you can try running at higher RPM to see if you can get it to catch more. I don't know that there's standard advice as to filtering quicker or slower to go faster and catch more of it.



That's correct - change the percentage to 10% to calculate for 10% LC.
When I change to 10, why does the calculator change from 6 weight % bleach to 10 trade % bleach? I don't know what "trade" is.

Thanks again for the advice
 
I think it's just a different way of calculating the bleach percentage. I wouldn't worry about that shift - if 10% is in there, you should be set. :)
 
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Test this morning:

Chlorine 8
pH 7.5
TA 100
CYA 30

I test at 8am and 8pm each day.
My target for chlorine is 12 during SLAM so this morning I'm adding 128 oz. of 10% (it was 68 oz. last night).
I run the pump at 2000 round the clock except when adding chlorine. I raise it to 2500 for an hour when adding chlorine.
I brush a few times each day. I have a hair net on the skimmer basket. The water looks lighter each day and the very start of going from light green to blue.

I understand it's a process and know the sand filter is the slowest, absolutely slowest at filtering. Yesterday, after backwash, I added 1 1/2 cups of DE following instructions.

I just want oversight from the group and ask for any advice I can get ... THANKS
 
If you can test more often, that will make the process go quicker. Life is what it is, and we can't babysit our pools all the time, but the more often you can add to keep that FC up at 12, the faster everything will die and stay dead. Then it's just a matter of the filter taking out the cloudiness. Otherwise your plan is just right. If you notice the FC is below 10, before you add, you can test the pH and add muriatic acid to bring it down to 7.2. That will help as well. Otherwise ignore testing for pH as at 10ppm FC and higher the test bleaches out and will read falsely high.

Photos will help keep track of daily progress. If you feel like sharing, please do - we like seeing the green-to-blue transformation. :)
 
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