Not getting a CYA reading

rnaval

0
Aug 13, 2015
60
Melville, NY
Pool Size
33000
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
Filled water from the pool to the 7ml mark, Added the R-0013 to bring it up to 14ml. Mixed for 30 seconds. Transferred solution to the small comparator tube and the black dot never disappears. Pool has maybe 1 foot of water that’s been added new. Trying to SLAM but can’t figure out what the FC level should be. It’s currently at FC level of 7 ppm.
 
I assume the pool pump has been running several hours and the water is well mixed.

If so, you have low to no CYA in the water. If the sample has 0 cloudiness, then add 30 ppm CYA using the sock method. If the sample at least was cloudy, add 20 ppm CYA.
 
Did it ever get cloudy at all, or just stay clear?

For a SLAM, less than 30 CYA means 10 FC.

If it got a little cloudy, consider the now CYA to be 10. Add 20 CYA. If it's clear, add 30 CYA. Either way, the goal is to get to 30 CYA. Then your SLAM level is 12 FC. You don't have to wait to add it and have it dissolve.

SLAM at 10 until you get some CYA in there, then move up to 12 FC.

The good news for you is that you don't need CYA after dark, so if you dose and brush this evening, it'll kill algae all night long without losing any chlorine to the sun.
 
Add the CYA by using what we call the sock method. Get an old sock (no holes) and put the measured amount of CYA you need. Tie the sock closed and either suspend it in front of a return (hang it from your brush pole works with something weighted on the deck) OR if it still allows flow thru the skimmer, place the sock in the skimmer. Every 15/20 minutes give the sock a squeeze to speed up the process. Please DO NOT follow the directions on the container of CYA to just pour it into the skimmer and don't just toss the sock in the pool as the CYA is acidic and can bleach/stain pool finishes.
 
It is called Stabilizer or Conditioner. Walmart, Home Depot, Lowes, Pool Stores, Amazon carry it.

After you SLAM and start to use your SWCG, you will want to raise your CYA to 70 ppm. With your size pool, you will need 20 lbs of CYA. Amazon sells it I believe in 25lb boxes. PuriTech. That would be a good deal for you if it can be delivered soon.
 
CYA protects the chlorine in the water from the sun. Without it the FC has a half life of 50 minutes. With a SWCG, a CYA of 70 ppm allows your SWCG to run more efficiently.

Have you never added CYA to your water before? A pool without CYA but FC above 1 ppm is very harsh on eyes, hair, clothing, etc.
 

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Nope never added before but I probably didn’t need to because I just converted to SWCG last year mid season. So I have chlorine tabs left over from last year, dont they have stabilizer in it? Is that an option?
 
If you were using trichlor then you were adding stabilizer.

Using tabs to increase your CYA in a short period of time is not viable. You can use them later to add 10 ppm of CYA when needed. Be aware they are very acidic so you need to monitor pH.
 
I read that you shouldn't backwash for a week after adding CYA, how do I get around this? I'm in the middle of a SLAM and need to backwash daily. Also, this is what I found on Amazon for stabilizer, 25 bag, brand named "In the Swim" for $94. Local HomeDepot and Lowe's seem to be out of stabilizer.


Is this what I should order?
 
If you add using the sock method, you can backwash as needed. Plus, you should be waiting until your filter pressure rises by 25% over clean pressure before backwashing.

Puritech is brand via Amazon that many use.
Stabilizer
 
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On a different note, is there a way to address a leak in the plumbing if I’m losing half an inch off of water in the pool daily? Meaning without digging it all up?
 
Found the filter was dripping from the drain, it was only a slight leak, hard to imagine it could lower the pool water level that much but I will monitor and check over the next few days.
 

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