CYA at 100, ok?

azdaren

Member
Jun 9, 2010
20
Ok I just started reading the forum a couple days ago. Using Pucks to chlorinate my water for years. My pool always looks great as I do test every/every other day, but only test for FC / PH / TA. Had water tested yesterday at Leslies for CYA and was told its at 100, ouch.

Here are my current #'s

FC 4-5
PH 7.5
TA 100
CYA 100

Using the pool calculator, it says my FC should be from 8 to 13. Does this seem high? I always shoot to keep my pool at 2-3.

I will be ordering a test kit this week so I can more accurate #'s. These are from one of the taylor test kits that gives a range based on the colors.

I had my pool acid washed and refilled last April, so the high CYA is definitely from using the pucks im guessing?

Thanks,
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,880
Silver Spring, MD
Welcome to TFP!

There are two issues here. The first is that pool store water testing can occasionally be way off, so it is difficult to decide how much to believe that test result. The second is that most common CYA tests read levels above 100 as 100, so if the test result is correct, your actual CYA level might be much higher than 100.

Assuming your CYA level really is 100 or higher, you should replace water to get the CYA level down below 100. Very high CYA levels present numerous problems, such as requiring extremely high FC levels.

The required FC levels depend on your CYA level. CYA buffers chlorine, reducing its effective strength, so you need to raise the FC level as the CYA level goes up to compensate.
 

JohnT

Admin
Mod Squad
TFP Expert
Apr 4, 2007
9,475
SW Indiana
Welcome to TFP.

Running with your CYA at 100 is a problem. You need to verify that you are at 100ppm and not a lot higher. There are testing issues that make the test inaccurate at high levels. You can dilute a sample with tap water 50-50 and your CYA reading will be close to half of your real reading. That will help you nail down where you are.

The higher recommended chlorine level is fine, and you will never notice it. A fixed percentage of your chlorine will be bound with the CYA, so if the CYA gets, too high, your 2-3ppm FC may perform like 0.5ppm when it comes to sanitation. Running the higher level will not be noticeable to bathers.

The best solution is to drain about 45% of your water and replace it, but you are not in an area where water is plentiful, so the higher FC levels may be preferable until your CYA naturally lowers due to splash out.

Jason posted before me, but we described the situation a little differently, so I'll post mine anyway.
 
G

Guest

Since you are in Phoenix, and R/O is available, you might call and get some info. I can give you a referral, if you wish.

Welcome to the 'page!
 

PoolGuyNJ

TFP Expert
May 20, 2007
3,192
South Central NJ
45% at one shot, may be excessive in more than one way. High water tables and pool types have different safe low water levels for dilution to prevent pop ups and floats of the structure.

In order for us to suggest the correct actions to take, wrt the dilution process, we need to know some addition information.

Pool type
Where to dump excess water
Can you system do this?
Drainage areas. High water tables make life a little interesting.

Pictures help. Equipment pad, pool, path to drainage area are particularly telling. Descriptions help too.

Scott
 

azdaren

Member
Jun 9, 2010
20
Thanks for the replies.

I have ordered my kit, hopefully I get it B4 the weekend.

Looks like I have some draining / refilling to do this weekend.

What is R / O ? Reverse Osmosis?

Thanks,
 

azdaren

Member
Jun 9, 2010
20
In the past I have drained water from my pool via the pressure release valve on my filter housing. I just run a hose to a cleanout in my house plumbing.

OK?
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,880
Silver Spring, MD
Yes, RO and R/O stand for reverse osmosis. RO is a treatment that removes nearly all of the dissolved solids from the water. It is handy any time you have extremely high CH or CYA levels and water is expensive or needs to be conserved.

Pumping the pool water to the sewer system is allowed most places, but not everywhere. Aside from the question of local rules, it is fine.
 
G

Guest

Yes, R/O is Reverse Osmosis. It is not available in all parts of the Country (yet!), but it is available by you, and is an option.
 
G

Guest

Same process; just on a much larger scale (and way more efficient than what is under your sink!)! The technology has been around for a very long time, but is just now being put to use by a handful of people who have seen what it can do to pool owners with high CH (among other things) and in areas with water restrictions and/or high water tables, to name a few. It is not available everywhere yet, and probably won't be needed in areas where water is plentiful and CH levels are low. In the southwest, where these conditions exist, it is starting to gain acceptance and growing.
 

azdaren

Member
Jun 9, 2010
20
Ok so I diluted my water 50% with tap water an had leslies test my cya again, still came back with a reading of 100 or more. I think I'm going to wait for my test kit and test it myself before I do any draining/refilling.

Could my cya level really be that high? After diluting 50% with tap water an still getting a reading of 100+, that would put my cya at 200+, wow.
 

Richard320

TFP Expert
LifeTime Supporter
Jan 6, 2010
20,852
San Dimas, CA (LA County)
azdaren said:
Ok so I diluted my water 50% with tap water an had leslies test my cya again, still came back with a reading of 100 or more. I think I'm going to wait for my test kit and test it myself before I do any draining/refilling.

Could my cya level really be that high? After diluting 50% with tap water an still getting a reading of 100+, that would put my cya at 200+, wow.
Yes, it could.

When I first tested my pool I diluted and was still off the scale. Diluted again, got something like 220. I later found out that cool temperatures make it read low, so it was probably higher. The previous owner and his useless pool service liked pucks in a floater. The pool was supposedly replastered and filled with fresh water two years ago.
 

azdaren

Member
Jun 9, 2010
20
Got my test kit yesterday and did a full workup this morning. Here are the results.

FC 6.5
CC 0
pH 7.4
T/A 120
CH 650
CYA 160


Not too thrilled about the thought of draining/refilling %75 of my pool. Do I really have any other options?