Newbie to Site, annoyed by CYA :-)

barkley94

Member
Jun 22, 2020
13
Prosper, TX
Had a friend at work recommend this site last year. I kept doing my normal chlorine tabs and shock. Now I find myself annoyed with high CYA levels, high calcium levels, and needing to drain significant amounts of water. So, a year later I am taking my friends advice and educating myself with this great site.

Test kit came today. Tried them all.

FC - 9.5
PH - 7.8 maybe 7.9 so hard to tell exactly
CH - 550
TA - 190 :-(
CYA - 100, maybe 110.

I did the TA 2 times. Both times same reading. I have another test kit I've used in the past and it gave 120 both times.
I'm surprised two kits are this different. Old kit is Pentair Rainbow.

Nothing else was surprising. Knew CYA was high which is why I have chlorine high right now.I assume first order of business is drain a lot of water and refill untill CYA comes down.

Pool is 25k gallon pebble tek with spa.
 
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Yup, not much to work on until CYA is at an acceptable level. It could be even higher than 110. You may want to try diluting sample by 50% then double the reading to be sure.

TA is not a biggie, it will come down as you add muriatic acid to lower the PH.

If you would, add all your pool information to your signature so the experts can better help you. Pump size, swg or not, type of filter etc. Settings then Signature.
 
OK, been a couple of weeks. Completed test Just Now:
FC - 2.5
TC - 2.5
PH - 7.4
CH - 600
TA - 140
CYA - 60

Having a hard time keeping enough chlorine in the pool. Part of it is I'm just getting used to using the liquid chlorine now that I have completely stopped using tabs and shock. Need to get used to adding it daily.

Chlorine is hard to find right now in Wal-Mart and other stores locally, luckily pool store started to carry it so I can get 12.5%, but it's a bit on the pricey side. Read some horror stories of people grabbing bleach at thei rlocal store that had chemicals causing some pretty ugly issues with their pool.

PoolMath app says to add about a jug of bleach to get the FC up from 2.5 to 7 so that is the plan tonight. Will keep a closer eye on chlorine daily going forward.
 
Normal FC burn off is 2-4 PPM a day. I was just reading before about the 100 year drought hitting you guys so it very well could be a bit more this year, at least now during the hottest part of it. If you suspect any funny business going on in the water, perform an Overnight Chlorine Loss Test once the sun goes down. If you lose more than 1 PPM with no sunlight, it will be SLAM Process time.
 
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I've been testing multiple times daily and have been successful at getting my readings all within range, but when I looked in the pool this evening I see green algae developing in corners and on the bottom. frustrating, but I suppose coming off of the situation I was in doing a SLAM was going to be a part of this process.

Latest Readings
FC 7.5
CC .5
TC 8
PH 7.3
CH 500
TA 90
CYA - Didn't Test today but assume it remains at 60

To get to 24 FC for SLAM I need to add 80 ounces of 73% Cal-Hypo or 450 ounces of 12.5% bleach. Looks like the main downside of adding cal-hypo is cloudy water, and it will add some calcium, but only add 12 to my CH reading.

Any other downside to adding the cal-hypo?
 
I've been testing multiple times daily and have been successful at getting my readings all within range, but when I looked in the pool this evening I see green algae developing in corners and on the bottom. frustrating, but I suppose coming off of the situation I was in doing a SLAM was going to be a part of this process.

Latest Readings
FC 7.5
CC .5
TC 8
PH 7.3
CH 500
TA 90
CYA - Didn't Test today but assume it remains at 60

To get to 24 FC for SLAM I need to add 80 ounces of 73% Cal-Hypo or 450 ounces of 12.5% bleach. Looks like the main downside of adding cal-hypo is cloudy water, and it will add some calcium, but only add 12 to my CH reading.

Any other downside to adding the cal-hypo?
How'd your CH go down from 600 to 500 without losing a like percentage of CYA? Has it been raining? Replacing water?
 
Good question. Since I got CYA down to 60 I have not drained any water, but we've had rain and I have added fresh water including a couple of inches last night. Can't explain why the CH is down other than maybe my 600 test was bad? When I started this initially on June 26 CH was 550. So after draining and refilling to get CYA from 100 down to 60, seems reasonable that the CH would go down as well. Seems like it should have gone down more.
 

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Had a friend at work recommend this site last year. I kept doing my normal chlorine tabs and shock. Now I find myself annoyed with high CYA levels, high calcium levels, and needing to drain significant amounts of water. So, a year later I am taking my friends advice and educating myself with this great site.

Test kit came today. Tried them all.

FC - 9.5
PH - 7.8 maybe 7.9 so hard to tell exactly
CH - 550
TA - 190 :-(
CYA - 100, maybe 110.

I did the TA 2 times. Both times same reading. I have another test kit I've used in the past and it gave 120 both times.
I'm surprised two kits are this different. Old kit is Pentair Rainbow.

Nothing else was surprising. Knew CYA was high which is why I have chlorine high right now.I assume first order of business is drain a lot of water and refill untill CYA comes down.

Pool is 25k gallon pebble tek with spa.
I had the same issue. My CYA was off the charts🤦🏽‍♀️ I only have a 10x30 Intex and it’s draining as I’m typing.
 
Started the SLAM process Tuesday at 9 pm. Added Cal-Hypo and did the initial brush of the pool that night. Next morning tested FC at 25. Brushed multiple times on Wednesday but did not test during the day and let FC dip down to 18.5 by 8 pm Wednesday night. Put more Cal-Hyp in and brushed one more time that night. At 10 pm I tested FC at 26. Brushed one final time and could see white powder comin gup off the bottom. Would the Cal-Hypo sit on the bottom for 2 hours, or would this be dead algae, or possibly a bit of both? Got up and tested this morning and FC is actually up to 27. This leads me to believe the test at 10 where FC was 26 was low because the cal-hypo had not fully cycled through the pool. If that's the case I guess I answered my own question from above about pros/cons of using the Cal-Hypo vs liquid bleach for the SLAM process.

Pump has been running 24x7 and I plan on testing multiple times today as I brush to make sure FC level stays at/above 24 (CYA is 60). Assuming FC stays high would final step be to do the overnight test tonight, and start the burn down process tomorrow?

I didn't have a huge algae problem to begin with, just "some" beginning to develop. Does a 48 hour SLAM seem reasonable to clear this up?

I need to invest in a vacuum. I have a robot cleaner but putting it into water with FC thi shigh is not recommended so I'm doing my best to brush everything to the drains to be sucked away.
 
First indicator is that the water is clear -- and the walls. Even after you brush. If that passes, then
test FC & CC and if CC is .5 or less, then
Run the overnight loss test.

If you pass all three you are done. If you only had a few patches of algae but the pool was otherwise clear, it shouldn't take but a day or two. People can turn a black sludge pit into a clear pool in a week.
 
Thanks Richard.

I did go grab a vacuum to hook to my skimmer. Seems like a good tool to have anyway and I like toys so just vacuumed and brushed the pool. The water looks very clear. Did the FC test and it measured 23.5 which is down from 27, 4 hours ago. CC was below .5. I put 13 ounces of bleach in to bump it back to 24 and will do another brush later today, and then do my overnight test tonight. I'm right on the verge of needing water added to the pool but I think it will make it til tomorrow after I verify the overnight test.

BTW, Leslies has buy one get one free right now for those looking for a good deal on 12.5% bleach. $11 for 4 gallons was a pretty good deal ;-)