How many pools with CYA over 100?

Shane1

LifeTime Supporter
Apr 29, 2010
621
Buckeye, AZ 85326
I have several questions for pool owners with high CYA (over 80ppm).

1)How many of you have high CYA over 80ppm?

2)How long has your CYA been over 80ppm?

3)Do you backwash?

4)Have you had algae issues?

5)What is you pool finish: plaster, pebble, vinyl or other.

Thanks
 

anonapersona

TFP Expert
LifeTime Supporter
Nov 5, 2008
2,598
Not now, but when I came here I had CYA over 100, up to 150 as far as I know, based on strips.

No backwashing ever, cart filter. But the pool was probably nearly drained and refilled after Hurricane Ike to recover so fast from being black water. It was clean a week later when we saw it again. With pucks and shock I ran it back to 150 CYA in a matter of months.

Yes, there was algae, mossy green algae in cracks of the rocks on the steps, flat green algae on rock coping, waterfall rocks were very very green, and some faint algae on the shady side from time to time. Never bad anywhere, the water looked nice, but green here and there.

Plaster pool, rock waterfall.
 

Beez

LifeTime Supporter
May 19, 2009
785
Dallas, TX
When I inherited the pool 2 years ago the CYA was well over 100. Within a month of buying the house I had my first and only algae outbreak. The next season, spring of 2009, I found TFP and the BBB method and haven't looked back since. I dare say I will never have algae again!

If you really want to know the percentage of high CYA pools that develop algae, especially pool store customers accustomed to chlorinating with pucks, just scroll through the Algae forum on this board.
 

lightingguy

LifeTime Supporter
Jun 17, 2010
513
Glendale, CA
When we got rid of our pool service our CYA was in the 150 range. We maintained a low FC level as per pool store and quickly developed an algae issue that was very difficult to shake.

I've been letting it come down on it's own. Tested last week around 95.

Have kept the FC up in the 6 - 13 range and have been problem free algae wise for 6 months or so.

I must say I'm kinda on the fence on the issue. Having it high allows me to add chlorine less often (The suggested FC range is bigger so I have more room to float in it) Since I dont have a real cover, get tons of sun and have some schedule issues that make daily maintenance impossible I'll probably aim for a CYA a little on the high side. (That's not advice by the way)

My guess is the more organic matter your pool collects the less advisable high CYA is, since the nature of your chlorine usage changes. (Protecting it from sunlight = good, protecting it from organic matter = bad)

If you're wondering about letting yours come down with time, rather than replacing a substantial amount of water - for me it hasn't been a problem, but you probably have to accept the possibility that it could be.

DE filter, I dont really backwash. I break it down and thoroughly clean it 3 times a year.
30 year old Plaster
 

Richard320

TFP Expert
LifeTime Supporter
Jan 6, 2010
22,049
San Dimas, CA (LA County)
I do! I do!

Last time I tested, about 10 days ago, I was still at 140. That's as close as I can tell, since I dilute 50/50 with tap water. It has been higher than that since at least last October when I bought the house. The filter's been backwashed once so far. I have pumped out some water and diluted with rainwater (drought year and all that) too. Never had an algae problem, but I keep on top of the levels knowing that if I do get one, I'll have no choice but to drain or try to get reverse osmosis done - closest R/O service is 2 counties away. The pool is plaster. It was supposedly redone 2 years ago.
 

lightingguy

LifeTime Supporter
Jun 17, 2010
513
Glendale, CA
Richard - What's your typical FC count?

I'm averaging 1.5ppm per day with warm (88-90*) water, full sun, and 3 ppl for 90 minutes or so per day.

I have some of those ridiculous sun ring things as well as a partial cover.
 

Richard320

TFP Expert
LifeTime Supporter
Jan 6, 2010
22,049
San Dimas, CA (LA County)
lightingguy said:
Richard - What's your typical FC count?

I'm averaging 1.5ppm per day with warm (88-90*) water, full sun, and 3 ppl for 90 minutes or so per day.

I have some of those ridiculous sun ring things as well as a partial cover.
Seldom gets above 17; only when I get lazy and don't measure the chlorine but just eyeball half a jug or whatever. Typically it's kept between 12 and 14. It gets sun all day long, and a lot of aeration because about 20% of the flow goes through the hot tub section.
 

loop_pea

LifeTime Supporter
Jul 11, 2010
156
England, UK
Me too. The pool is around 90 ppm CYA. We do a lot of backwashing when the pool is being used, daily sometimes. Without the backwashing, the CYA would be closer to 120 based on the amount of trichlor/dichlor we've got through. We got from 0 to 80 CYA in about six weeks (!), but haven't had any algae thankfully. The pool is seasonal and usually emptied annually, so we get away with it.
 

chem geek

TFP Expert
LifeTime Supporter
Mar 28, 2007
12,083
San Rafael, CA USA
When I first got my plaster pool 7 years ago, I used Trichlor pucks/tabs in a floating feeder. I had a mostly opaque electric safety cover and the pool wasn't used every day so the chlorine usage was low at around 0.7 ppm FC per day. Nevertheless, after one-and-a-half seasons of use (around 11 months) my Cyanuric Acid (CYA) level went from 30 ppm to 150 ppm. I usually kept the FC level at around 3 ppm. I had an oversized cartridge filter, so no backwashing and only once-a-year cleaning and I had a pool cover pump that put winter rain water into the drain (not into the pool) so there was very little water dilution. In spite of using algaecide (that was mixture of Polyquat and linear quat), though only every other week, after getting near 150 ppm CYA my pool started to get a higher-than-normal chlorine demand followed by dull and then cloudy water as an algae bloom was developing. The acidic Trichlor pucks also rusted mounts for stainless steel bars below the water line.

Since that time, I've been using 12.5% chlorinating liquid and have had my CYA at 30 ppm and more recently at 45 ppm and not had any algae in spite of 3000+ ppb phosphates in the pool except for one time I let the chlorine get to zero accidentally during one spring startup (really just heating the pool since it is still chlorinated and circulating in the winter since it doesn't freeze).

Some pools will be lucky enough to get a high CYA level without a proportionately higher FC level and not get algae, but most will unless an algaecide is used or the nutrients are very low. Even then, the risk is still higher than simply using an appropriate FC level relative to the CYA level.
 

Mona

LifeTime Supporter
May 23, 2007
91
SE Minnesota
oh,oh, me too, me too!! Okay, not anymore, but I did. It was about 150, now is 70. Inherited the pool with the house, it will be 5 years the end of August. I knew nothing!!!!! Was told to put these tablets in the skimmer and vaccuum as needed. We had like 3 days of rain and the pool was a very deep green! :) Looking back, since now I'm a little smarter, while vaccuuming since we had bought the place there was an algae bloom starting. I was ready to rip that dang thing right out, over $300 spent within a month and hours of cleaning that mess up. Closed it up end of Sept and started reading whatever I could find for boards that winter. Which eventually led me here. I preach BBB and pool water chemistry to anyone that wants to learn. :) I want anyone thinking about getting a pool to learn correctly first. I didn't drain/replace to get mine lowered, it's just the initial partial drain in the fall, some backwashing and waste when too full due to rain. It's eventually come down, a few more years and it will be right where I want it. Now hopefully I can get my TA to do the same, which now it's sitting at about 160. Was up to about 200 or more when I started. I've not had any problems the past 4 seasons, because I know what I'm doing now.