CYA out of control, now what???

Oct 21, 2008
51
Terre Haute, IN
Before learning a lot from this site I had a bad green algae problem where I went through numerous shockings across three weeks using trichlor, dichlor, etc and used some Cheleated copper.....After following a post in here and keeping FC at 15 (from Bleach) for 3 days it dissappeared!!!......Algae is gone but a bluish color exits to where I cant see the bottom....I took my water to a pool store (TFT kit on xmas list ) and my specs are as follows:

PH 7.8
FC 3.0
TA 150
CYA 100+ (I WAS SHOCKED I DIDNT PUT ANY CYA IN FOR OVER 3 MONTHS)
Ch: ? Sorry that did not write that one down.

I realize now after my education from this site and the pool calculator the side effects of large quanities of certain shock chemicals adds CYA. Short of a drain/rebalance is there any side effects running with this 100 CYA level and just keeping my FC level higher? IF so, a really high CYA using Bens best guesstimate is it practical at 100CYA and the 8FC level??? Does it require a lot more bleach to move FC levels with this kind of ratio? If it safe for my kids/bathing suits??? IF the only side effect is just higher doses of chemicals then it may be cheaper to do a partial drain/refill....I did drain about 10% of the pool to help and the PH dropped to in range now 7.6

---Also, Is my funny colored water due to this from my high CYA or Copper from the Algaecides? Any help would be greatly appreciated.

Oh, as a side note to support the teachings here DO NOT trust test strips.....My numbers were way off and my CYA was not even registering!!!!! I even made them test twice at the pool store to verify this out of control CYA (I was between 0 and 30), and my PH was showing low (7.2, theirs was 7.8 ) this was from the same bottle of water both test methods!!!
 
Well, it sounds like you are going to need to do some draining and replacing on your water. Some people do try to stick it out with high-ish CYA levels in non-SWG pools. You could probably get by if your CYA was 70 or even 80 ppm. But the fact that your CYA came back as 100+ tells me that we aren't really sure what the true level is other than the fact that we know it is at least 100 ppm. Most tests won't read above 100 anyway. Who knows? It could be 150 ppm! Unless you truly know what the exact number is, there can be no guarantee that you are getting your FC to the correct level for shocking purposes. Does this make sense?
 
Your right, I should not count on it just being 100 it could be 150, i need to at least get it to a readable level, did not think about how much over 100 I may be!!!! Yes your message makes sense and if I do a partial drain/refill (also trying to prep for winter in the midwest) to get me down to say where I can read a true 80....Thus still needing a higher FC level for maintenance and for shock. Still some questions though when I get my CYA to 80 (we get a lot of rain in the midwest spring time so I will get some free dilution).

1. Does that mean that its safe for swimming at these kinds of FC levels (7)and CYA (80), (keeping PH in check)???
2. Will it require more chemicals to move points of FC at these levels (using bleach)???
3. And the last question about water color, is the result of high CYA or High copper do you think (I dont have a copper tester, I do not see signs of scaling though)??? Not even sure if high copper equates to scaling.
4. One last new question, throughout all this algae killing I also got leaves in the pool I'm sure are at the bottom. I cant see to clean them out due to the bluish tint, if they sit on the bottom all winter will they stain my liner? Wanting to go ahead and close for season but dont want to make too much of a mess for next spring!!!

Hard lessons learned trying to cleanup the imbalance after fighting Algae....Thats okay learning a lot from TFP!!!!

THX!!!!!!!!!!!!!!
 
It sounds like a copper reaction. Start with the partial drain/refill and get your balance back in check. You may still need to use something to deal with the copper but it may also be diluted to the point of not being a concern.
 
Sounds like a good enough plan to do a partial drain thus taking out some of the tainted copper and high CYA water....Gonna start with a 20% drain and refill and see what happens, may hold whatever the reults are after this drain for winter...When someone gets a chance and is knowledgeable about my 4 questions please respond (related to my mess), Thx for the two people who responded thus far....Got confirmation to at a minimum do a partial drain/refill to get my CYA to a known value.....
 
Higher FC levels are safe at higher CYA levels. As long as your FC level is at least at the minimum FC level and lower than the shock level for your CYA level, as listed in this chart you should be fine. CYA "inactivates" much of the FC, so the effective FC levels are more or less constant within each of the columns of that chart.

Reaching higher FC levels in the first place requires more chlorine, which can be quite dramatic when shocking at high CYA levels. However higher CYA levels reduce the amount of chlorine lost to sunlight dramatically. So maintaining a higher FC level often takes less total chlorine at higher CYA levels.

CYA does not color the water, even at very high levels. CYA can, however, reduce the effectiveness of your chlorine, potentially allowing algae to color the water. Copper can color the water, though that is quite rare. Usually when copper does color the water it turns it a clear emerald green. If the water is at all murky it is probably algae.

Leaves left over the winter can cause organic staining. Organic stains will fade over days to weeks and eventually disappear after you open the pool again in the spring.
 
Though having leaves in the bottom of your pool also makes for a breeding ground for algae. The cleaner you have your pool at closing, makes a much better opening in the spring.
When we moved into our house 3 years ago the CYA in the pool was 135. I did not do a partial drain, with some draining for closing, rain, backwashing, I knew it would take time but I would eventually get it down. It was about 75 this year and will get it down to 50 through next summer. I just ran higher FC in line with the CYA. I also used a Poly 60 for extra protection.
 
A few more questions to this thread, Thanks to everyone who responded!!!!!!

Gonna do as suggested and go ahead and close and run with the CYA I have.....As indicated it is going to cost too much to take my pool to a true shock level at these ranges, but if I keep my FC where it should be and above and proper extra Algaecides (per Mona) I'm reading I should be okay...

When I get my testkit I am gonna do a 50/50 mix of tap water and pool water to help dial in where I'm truly at CYA level.

Out of curiosity anyone running with high CYA/FC does the pool stay clear (not hazy)? Mine is still a blue color and I thought I identified some haze in it last night. Wondering if my sand filter is having trouble filtering out all that dead alage. Its been cold here(50's at night) and I have been running the pump 24/7 (7 hour turnover)....I have been backwashing it like daily and its been clean at the start of backwashing the last two days..Appears to be algae free for almost a week now. Gonna change the sand to zeobrite in the spring. I just bought this house/pool so I dont know how long and what is in the current sand filter. Hoping that will fix the funk still in there come next spring.

Any insight about my color and possibly clarity issues after I get my blue out running with this kinda CYA/FC levels would be appreciated. As of now the only negative thing I know of is the cost to take it to a true shock and extra risk of big problems should Algae roar its head again. IF I was to get crazy and try to take it up to like the 30+ FC level to shock it does it take a long time to come back down for safe swimming???? Not sure since I would have a strong protector base in it to not break it down, does it take multiple days to swim again?

Guess it leads me to my final question in this thread, what are safe levels of FC to swim in with a 100+ CYA...I've found threads talking about how CYA increases means that its safe to swim with a higher FC level, but then what becomes the new threshold for safety after a 30+ FC shock and a 100+ CYA???? I know most people with the recommended balance levels shoot for below 5-10FC for swimming again, but what about if your in the situation I'm in or Mona discussed????
 
The blue hazy water is just the remains of the algae. It seems to take forever to clear, but it will clear quickly when it goes. It usually goes faster if you brush or vacuum a couple of times a day to get the crud up where the filter can clear it. Try a dose of polyquat algaecide which is also a clarifier or just put a double dose of cheap clarifier in and it will speed you along.

You are about 60miles NW of me, and my water is cold enough that I'm not too concerned about algae anymore. I'll be closing Sunday ahead of anticipated lows in the upper 20's next week.

Depending on your cover, you can take advantage of our winter rains in Indiana to dilute your CYA for free. I run mine at 40-45ppm, and I seldom have a measurable level by spring. I have a mesh cover and have to drain two or three times over the winter.
 
john, youve peaked my curiosity, seems my cya issue will be null come next spring due to dilution. so i guess my potential concerns won't be an issue...Thought of some dilution with my mesh as well but not that much!!! Good to know i will get a fresh chance to start over for free (rain dilution) come next spring!!!

Since we both have the same basic weather, how do u drain mid winter???? Do you just have a seperate pump and leave the core system winterized??? Have u ever just let it get to the top and overflow then? any risks that way should it try and freeze? Guessing most of your dilution comes from our Indiana spring rains.

Thx!!!!
 

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Hello Investindy! I am down in Southern Indiana, just across the river from Louisville, KY. I had a high CYA (100+) , at the start of the summer, thanks to my PS. Luckily, I ran across this website. I had to do several partial drains and fills, working my way down to CYA levels of 80, then 70, 60, and finally finishing the summer out at 50. Of course, the bleach requirements were higher at those levels, but I can assure you, my pool water was beautifully clear and sparkly the whole time. My pool was closed today. Once I open in early April and do my "top-off", I am hoping my CYA level will be even lower (30-40). We didnt have much rain during the summer, but what we had, did not make a measureable difference in my CYA levels; it took partial drains and fills to do the trick. This website is the absolute best! I have used nothing but Bleach most of the summer. If it wasn't for the TF-100 test kit, I would have closed an "un-balanced" pool, and had a mess in the spring.
 
investindy said:
Since we both have the same basic weather, how do u drain mid winter???? Do you just have a seperate pump and leave the core system winterized??? Have u ever just let it get to the top and overflow then? any risks that way should it try and freeze? Guessing most of your dilution comes from our Indiana spring rains.

My yard drops some behind the pool, so I just fill a garden hose with water and stick one into the skimmer
and the other as low as I can get it. The water level will siphon down to the bottom of the skimmer.

h2ctpdjl said:
Hello Investindy! I am down in Southern Indiana, just across the river from Louisville, KY.

I grew up in New Albany and went to school in Clarksville.
 
I have a similar problem as this thread (high CYA)....I read from JasonLion that if I have to go all the way up to shock that its okay to swim in it (39FC/CYA 100)...

My related question is though running with this kind of level will my pool hold in the 30's for a long time, thus essentially holding so I'm not wasting the money spent to get that high? I recently did what my pool store told me and thats why the high CYA so I have no logging of reality of breakdown times. If its safe and the stabilizer holds the FC why wouldnt you want to run with a high CYA? Minus the first time getting it so high, if it takes weeks to get back to 12FC why would that be considered bad and frowned upon by what I've read throughout TFP???
 
High CYA levels lead to a number of problems. None of those problems are insurmountable, but they are sufficient to make long term use of high CYA level problematic. When CYA is high the FC level need to be high, but high FC levels (above 15) interfere with the PH test, so it is difficult to maintain the correct PH with very high CYA levels. High CYA levels also mean that very dramatic amounts of chlorine are required if you get algae. It is also very difficult to measure high CYA levels with any precision. The best available CYA test only reads up to 100 and the other test are significantly less precise. If you don't really know what your CYA level is, you can't be sure that you are maintaining the correct FC level.
 
I should add that you can have high CYA levels with lower FC levels if you use a supplemental algaecide such as weekly PolyQuat 60 or maintenance dosing of phosphate removers, but these items cost extra money. Nevertheless, they are what are typically packaged together along with Trichlor in "no algae, guaranteed" programs from pool stores and manufacturers.

You have to be diligent, however, because missing a maintenance dose of PolyQuat or having the chlorine get too close to zero can result in algae growth that is VERY hard to get rid of using chlorine alone. You then are left with other difficult options such as using an algaecide with copper that can then result in staining. Of course, even with the chlorine-only approach you need to be diligent, but at least any algae development can be readily killed off with chlorine alone if the CYA isn't too high.

The difficulties Jason mentioned in his post plus the problems with the alternative approaches described above are why the chlorine-only approach is what is promoted for a Trouble Free Pool. If you add Borates to the pool, then this acts a bit as an algaecide like insurance in case the chlorine gets too low, but may not be as strong as using the more expensive approaches of PolyQuat or phosphate remover which is why we don't lower the minimum recommended FC/CYA levels even when using Borates.

Richard
 
this is a great post! thanks everyone! i have been searching this site for High CYA and how to deal with it and this was the best post by far!

Am a pool newbie! Just moved late last summer to a house in central NJ with a 17x33 inground vinyl pool and had it closed in Oct by a pool shop. i opened it myself last week and have found out (via this site over the last few days) that the chem maintenance schedule the previous owner had told me (2 trichlor tabs a week in a hayward autofeeder and aquachem (dichlor) shock every week or even every 3-4 days!) is probably why my CYA is so high (test strips said 100+) and i never seem to get FC over 0 (by test strips and OTO test). I have ordered TF-100 kit, for more accurate results, should be here this week! :)) So am looking to do a partial drain and get CYA down and start fresh by trying out the BBB method (off to walmart this morning! :)) Looking forward to doing this pool right, thanks everyone!!!
 
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