FC/CYA ratio at higher levels of CYA

Katodude

Silver Supporter
Aug 22, 2017
1,467
West Palm Beach/Florida
Pool Size
15000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
Sooooo.

I overshot my CYA. Was trying to get 80 and went to 100. Verified with dilution and straight. With dilution test it went to just greater than 40 but we round up so lets say 100 or just under.

Now I like to keep my FC at around 10% of my CYA. So is a FC level of 10 with a CYA of 100 the same as a FC level of 8 with a CYA of 80?

I just freaked out anyway and bumped my FC up to 16 anyway. But wondering what I should keep it at. It should not be a long term problem as my water is getting hot, and we are about to enter rainy season so its probably just a month long problem.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
39,675
Laughlin, NV
Pool Size
6000
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
Keep the FC at 8-10 ppm and all good. You get lots of rain and some overflow so CYA will drop over the next couple months.

When you do a pH test, read the result quickly. A FC near 10 ppm or above will mess that test up.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
18,020
Tucson, AZ
Pool Size
16000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Remember that for SWG pools we say the floor value is 5% of CYA. So at 100ppm, you need at least 5ppm FC. If you can keep up near 6-7ppm, you’ll be fine.

Full Disclosure - I spent two full seasons with an FC maintained at 3ppm and a CYA at 90-100ppm …. Never got algae or needed to SLAM. The secret is how much red pepper sauce you add to your …. Oh wait, that’s my hot wing recipe secret ….
 
  • Like
Reactions: onBalance

red-beard

Gold Supporter
May 27, 2019
1,108
Houston, TX
Pool Size
25000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite Pro (T-15)
Remember that for SWG pools we say the floor value is 5% of CYA. So at 100ppm, you need at least 5ppm FC. If you can keep up near 6-7ppm, you’ll be fine.

Full Disclosure - I spent two full seasons with an FC maintained at 3ppm and a CYA at 90-100ppm …. Never got algae or needed to SLAM. The secret is how much red pepper sauce you add to your …. Oh wait, that’s my hot wing recipe secret ….
Also not dunking your head below the water level...
 

Katodude

Silver Supporter
Aug 22, 2017
1,467
West Palm Beach/Florida
Pool Size
15000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
Not worried about pH testing, I have a pH probe installed that works really well.

But I think my pool just needs a higher level of chlorine. There is no way a FC of 6-7 would work for me. Black algae would start up pretty quickly. I like at least 10% of my CYA. I was just worried that once CYA gets that high do I need to go higher than 10%?

At a CYA of 70 or 80 10% seems to work fine for me.
 

red-beard

Gold Supporter
May 27, 2019
1,108
Houston, TX
Pool Size
25000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite Pro (T-15)
I'm running 9-10 ppm FC, with 70-80 CYA.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
18,020
Tucson, AZ
Pool Size
16000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
You need to lower your phosphates, add borates and stop peeing in your pool …
 
  • Haha
Reactions: clambert1273

Enjoying this content?

Support TFP with a donation.

Give Support

Katodude

Silver Supporter
Aug 22, 2017
1,467
West Palm Beach/Florida
Pool Size
15000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
You need to lower your phosphates, add borates and stop peeing in your pool …

So I know you are probably joking, but I actually do have a phosphate test kit and just checked phosphates which are 0. I also put in a bunch of SeaKlear earlier in the spring before I changed my filter. Even though my phosphate test back then also showed 0 the pool did cloud up for a few hours from the SeaKlear. It cleared up and 3 days later I threw out my filter and put the new one in.

I have about 30ppm of Borates (as accurately as I can tell from the strips). I dont have a problem upping the borates, will just need to drop my TA a little further before I do that. My pH has been steady but I guess it can alway be better.
 

red-beard

Gold Supporter
May 27, 2019
1,108
Houston, TX
Pool Size
25000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite Pro (T-15)
Why do you need to drop your TA before 20 ppm Borates? It will add less than 5ppm

 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
18,020
Tucson, AZ
Pool Size
16000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Phosphate remover will always cloud up even if the PO4 level is zero. Lanthanum reacts with carbonate as well as phosphate. And yes, just add the boric acid already and stop being such a noob ...
 
  • Like
Reactions: Katodude

red-beard

Gold Supporter
May 27, 2019
1,108
Houston, TX
Pool Size
25000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite Pro (T-15)
Matt, we all can't have 10 posts per day. I have to split my wisdom between here and Pelican Parts Forum...

BTW - Green Text = sarcasm...
 
  • Haha
Reactions: clambert1273

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
18,020
Tucson, AZ
Pool Size
16000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Only 10 per day, I must be slowing down in my old age …
 

Katodude

Silver Supporter
Aug 22, 2017
1,467
West Palm Beach/Florida
Pool Size
15000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
55 lbs on Boric Acid ordered!!! Duda was out of stock so ordered from bulk apothecary. Also added a lb of AA. Going to test a few stains that I have. (Not the ones from the pee, the other stains).
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
18,020
Tucson, AZ
Pool Size
16000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Did Bulk Apothecary give you a similar price to Duda? Seems like every business out there has shortages.
 

Katodude

Silver Supporter
Aug 22, 2017
1,467
West Palm Beach/Florida
Pool Size
15000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
$51 pretty good, then check out

$45 for shipping ouch.

Oh well, I just spent $200 for pre emergent for my lawn so who am I to judge.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
18,020
Tucson, AZ
Pool Size
16000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
$51 pretty good, then check out

$45 for shipping ouch.

Oh well, I just spent $200 for pre emergent for my lawn so who am I to judge.

Isn’t it crazy how much homeownership drains you?? I’m so ready for that “deluxe luxury apartment home community” where I own NOTHING and therefore am not responsible for anything that breaks or needs “maintenance”.

Of course there is the matter of the 4 little ankle-biters to get rid of first ….
 

Katodude

Silver Supporter
Aug 22, 2017
1,467
West Palm Beach/Florida
Pool Size
15000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
Isn’t it crazy how much homeownership drains you?? I’m so ready for that “deluxe luxury apartment home community” where I own NOTHING and therefore am not responsible for anything that breaks or needs “maintenance”.

Ugh, tell me about. True story, this is my first home (and I am not a young fellow). I was always a city dweller in a nice rental apartment. Never fixed or had to take care of anything except my wine cellar. Then I got married and had to buy a house. I did not want a pool, but my wife said no problem I have had lots of pools I will take care of it. So one green pool later. Pools stored for years, then pool serviced for years, all with a green pool. Guess who deals with the pool now.

1st world problems.
 

Enjoying this content?

Support TFP with a donation.

Give Support