beautiful pool turned dark green

[Britali]

You are on your way. Just need to get your pH down to do that SLAM.

 

[danielsonway]

Thanks for the encouragement and support.
I was able to bring it down to 7.5 today. Almost there!

 

[danielsonway]

Sep 2 Friday 10AM update:

FC = 0.5
CC = 0.5
TA = 50
CYA < 30
Cl < 0.5
pH = 7.2

I added 1 gallon MA 34.5% and 1 gallon bleach (10%) since yesterday evening.

 

[duraleigh]

Do the SLAM process. Follow the directions precisely.

Get your CYA to 30 ppm and immediately after adding CYA, start the process.

 

[danielsonway]

This is frustrating

I just put 4 gallons of liquid chlorine within an 1 hr. Testing within 10 min shows barely 3 for FC. How is this possible? Is my bleach bad? Just bought them today from Walmart. The earlier batch from Home Depot did not help either.

I'd appreciate any advice.

 

[Britali]

Chlorine does go bad. There is a whole thing on being able to tell freshness date based of of what is stamped on bottle. Will start with 2022 and then Julian date to show how fresh. I believe it starts to degrade if more than 3 months old. When I bought initially they were not new so reduced the 10% to 6% for calc’s. But may not be the expert way to calculate it lol.

 

[deanr]

Also possible something is consuming that CL. The correct amount to add is "whatever it takes to reach the prescribed level". There isn't any way to know how much that will be, if there is anything consuming CL in the pool. Just keep adding until you reach the SLAM level and it holds...

 

[danielsonway]

When I started the fight with algae I had CYA=90. I did water exchange and brought CYA down to 30.

But since then CYA went down to zero. Does that mean there is a leak? Where could that be? I just shut off my supply line (should have thought of this before).

Because CYA is too low and there is still algae (and the air temperatures have been around 105F), no matter how much chlorine I pour I cannot raise FC. Last night I added 1 lb stabilizer and 8 gallons of liquid chlorine. I measured FC=4 and CYA<30.
This morning CYA still zero and FC=1.

Do I need to start over? Just empty the whole thing and clean it up from ground up? Does the water table risk apply in Chandler Arizona?

 

[deanr]

Be patient. Understand that if you have a high algae (or worse, ammonia) load in your pool, it can take a LOT of chlorine to clear it up. Also keep in mind that when you add stabilizer, you won't be able to measure the change for up to a week or so.

Keep adding CL - go buy more today. Test your FC in the evening after the sun is off the pool so UV/CYA is not a factor. Add as much CL as PoolMath tells you to reach SLAM levels. Let the pump continue to run for 30 minutes or so to stir things up and test again. The FC will probably not be any where near SLAM level, so add as much as needed to get there again. Keep repeating that process all evening until you do reach the SLAM level. At that point, you can go to bed. You might realize during this time that you are short a case or two of CL.

Get up before dawn tomorrow, and check it again before the sunlight hits the pool. Add whatever CL is needed to bring it back to SLAM level, and start brushing. Keep checking during the day, and adding CL as needed. Hopefully the bulk of CL would have been added during that first evening, but you will be adding more. That's especially true if your CYA really is low. In that case, it can be hard to tell during the day if the FC loss is due to UV or algae load. But when the sun is down, you can be confident that FC loss is due to algae or other load that requires more CL. Just assume there is no upper limit to the amount that could be needed when you're adding in the evening to reach and hold SLAM level during the early stage of the process.

During this time, continue to add Pool Owner Patience. That's often the item in shortest supply...

 

[danielsonway]

Dear deanr - thank you. I appreciate the advice. Your tone stroke a cord in me. You must be an experienced educator. Thanks again.

My numbers are looking better. Though my pool is still greenish and very cloudy.
Cl > 5
pH = 7.5
FC = 12
CC = 1
TA = 50
CYA = 0



I can hardly see the 2nd step down in the pool. I'll continue to try to maintain FC=12. Is there anything else I should be doing? I am brushing but blindly so not sure how effective it is.

 

[jmastron]

Dear deanr - thank you. I appreciate the advice. Your tone stroke a cord in me. You must be an experienced educator. Thanks again.

My numbers are looking better. Though my pool is still greenish and very cloudy.
Cl > 5
pH = 7.5
FC = 12
CC = 1
TA = 50
CYA = 0

View attachment 451801

I can hardly see the 2nd step down in the pool. I'll continue to try to maintain FC=12. Is there anything else I should be doing? I am brushing but blindly so not sure how effective it is.

You're doing great. At this point, you can simplify your testing a bit -- I wouldn't bother with the OTO test (the color chlorine test using the test block), since the FAS-DPD test you're doing anyway is much more accurate. The pH test is not accurate when FC is >10 (that's one reason we lower pH before the SLAM), and don't bother with TA and CH tests for now; they aren't crucial to the SLAM process. So for right now, you can focus on the FAS-DPD FC test, along with the CYA test only until you've got it at the level you want.

When you do another Calcium Hardness test, make sure you do the 10ml version if you weren't; since you know your CH is high that'll reduce the drops needed drastically to get a result.

Once the SLAM is done and you're ready to switch to the SWCG, you're going to want a K-1766 salt test kit (unless it's part of the kit you have). I'd order that now, and test the salt level before putting any more in. It's not a good idea to rely on the SWCG's salt readout (especially when it's of unknown age/condition), and even non-SWCG pools often have significant salt levels because that's what all forms of chlorine break down to.

And as nice as it is to see pictures of your test kit, we trust that you're doing it right now, and I think we'd much rather see pictures of our pool day by day!

 

[Britali]

You are in great hands with these guys! Now that you are in SLAM, follow their guidance & know that it may take awhile. So try not to worry too much, make sure you have the chlorine to keep it up and don’t give up. You will see a difference and you will be oh so proud.

 

[danielsonway]

Thank you for the support. This is a great community.

There is slow but steady progress. I have plenty of liquid chlorine in stock at home now
Here are my measurements since last night. The pool is a little clearer. I can see the 2nd step.

220907 1:50AM FC=18, add none.
220907 7:20AM FC=14, add none. -> Lost 4 ppm in 5.5 hrs overnight.
220907 12:10PM FC=12, add 1 gallon LC. -> Lost 2 ppm in 5 hrs of day time.
220907 19:30PM FC=13.5, add none.

I do have the TF-Pro Salt with SmartStir (Smartstir is yet to arrive). I'll test the salt level once the SLAM process is complete.

 

[Texas Splash]

Sounds like you are doing well with the chemistry side and maintaining the proper FC (SLAM) level. Be sure you inspect and brush all areas of the pool. Leave nothing to chance where algae can hide. The SLAM Process will work. Progress is good!

 

[danielsonway]

Progress stalled. I have been doing SLAM for a week. Still it is consuming 3-4 gallons of LC and still very cloudy. Thinking of adding DE so I can see better and brush better.

220907 1:50AM FC=18, add none.
220907 7:20AM FC=14, add none. -> Lost 4 ppm in 5.5 hrs overnight.
220907 12:10PM FC=12, add 1 gallon LC. -> Lost 2 ppm in 5 hrs of day time.
220907 19:30PM FC=13.5, add none.
220908 01:30AM FC=8.5, add 3 gallons. -> Lost 5 ppm in 6 hrs of night time.
220908 7:00AM FC=17, add none.
220908 3:00PM FC=13.5, add none. -> Lost 3.5 ppm in 8 hrs of day time.
220908 6:30PM FC=12.5, add none. -> Lost 1 ppm in 3.5 hrs of day time.
220908 11:30PM FC=10.5, add 1 gallon. -> Lost 2 ppm in 5 hrs of night time.
220909 7:00PM FC=7, add 2 gallons.
220910 12:30PM FC=9, add 2 gallons.
220911 8:30AM FC=10.5, add 2 gallon.
220912 6:30AM FC=8, add 1 gallon.
220912 8:30PM FC=5, add 4 gallon.
220913 8:30PM FC=8, add 3 gallon.

This light would light up the whole pool, now it goes only half way.

 

[aussieta]

no one has mentioned it yet
but i wonder if previous owner switched to tabs because the swg was faulty
keep it in mind, when you finish your slam

 

[danielsonway]

Thanks aussieta. I am still working on SLAM. But when it is done, any idea how to check if swg is working properly? Would I do an OCLT?

Here are my latest test results:

pH = 7.8
FC = 16.5
CC = 1
CH = 900
CYA = 0

 

[aussieta]

there is a quick check where you set swg to 100% and take a sample from the return jet
which should be very high in fc
or once slam is over
you perform ocgt
where you measure the gain in fc overnight with swg set to normal output

 

[Bperry]

Thanks aussieta. I am still working on SLAM. But when it is done, any idea how to check if swg is working properly? Would I do an OCLT?

Here are my latest test results:

pH = 7.8
FC = 16.5
CC = 1
CH = 900
CYA = 0

Check your CYA again. It can’t drop to zero unless you replaced all the water. It may just be below 30ppm. Your CH number is also a bit worrisome. Any chance you have a water softener in the house?

 

[danielsonway]

Well, the thin tube is full and I can still see the black dot. So it is below 30. I did replace 2/3 of the pool water. Yes, I have a water softener.
We have had sand storms recently. The backwash came out very brownish yesterday.