Stabilizer

[Calcutta]

What is the downside of having too much stabilizer in the pool.
What PPM would be the absolute upper limit.
calcutta

[Watermom]

The downside to too much stabilizer is that you have to keep your chlorine extra high to keep algae at bay. You're not going to get a definite answer on what is the absolute upper limit. We typically recommend 30-50 for most pools, but there are many people who intentionally run with a higher cya than that. One of my co-moderators, Janet (Aylad) does just that because she says that with her location (Louisiana) and the amount of sun her pool gets each day, it makes it easier to manage her chlorine consumption. Probably the best thing for you to do is to repost with a current set of water testing results and let somebody here take a look. That will help you get better advice. Welcome to the forum!

[Calcutta]

Thanks for your reply.
I'm on the west coast of Florida, sub-tropical climate, 10,000 Gal. pool.
I really dont have a pool problem, but accidently added too much CYA to the pool. I dumped some water and got the reading down to 50 PPM. I have a salt water pool, take readings frequently, and have been blessed with literally NO problems in the 5 years that we've had the pool.
My neighbors say that I,m full of BS, but weve never had an alge problem, and have only shocked the pool 3 times
in 5 years.
The only problem that we've ever had is when airborne fertilizer got into the pool and raised the NITRATE level high enough that the chlorinator would/could not produce ANY chlorine. Again we had to dump half the pool to correct the problem.
For grins I took a water sample and had it tested with a Millipore standard plate. The reading was 10 CFU(colony forming units. Many municipal water systems have far more than this.
Again, thanks for the response.
Calcutta

[aylad]

A CYA of 50 is fine...just keep your chlorine at 5 or above, and you should have no problem at all. I don't know if you close your pool for winter or not--if you do, you'll lose some of the CYA when preparing it for winter. If not, (I don't), you'll likely see the CYA fall due to dilution (and the unexplained phenomenon of CYA dropping over the winter that some people on this forum, but not others, have experienced). Then you can run it back up to wherever you want it. Personally, in your climate, I would think 50 is idea anyway. (Then again I run mine around 80 intentionally and most people think I'm nuts! )

Janet

[Phillbo]

Read your Salt System's manual. Most want you to run the CYA at a slightly higher level. 50 may well be within the range they want but you may want to verify that.

[DennyB65]

I have an aquarite swg and the manufacturer reccomends a cya of 80-100!

[Poolsean]

I'm not sure of the chemistry behind it, but that's correct with SWG manufacturers... 60 - 80 ppm for Pool Pilot and chlorine levels at about 3 ppm is more than sufficient to maintain your pool crystal clear. All other water chemistry parameters considered to ensure proper water balance (Saturation Index).

Most commercial guidelines recommend 100 ppm as the maximum stabilizer level allowable in a public pool.

[waterbear]

In light of recent studies down I would set an upper limit of 100 ppm for a plaster pool since it has been suggested that higher levels can cause damage to the plaster surface. Remeber that any aggragate finish (DiamondBrite, etc.) is actually plaster

[DennyB65]

Speaking of stabilizer. Is there a reliable test for it? I don't trust my pool stores numbers on stabilizer as they seem to be very erratic. I have even had them test my water twice within a 3 day period and have gotten vastly different results. I would love some advice on this.

[chem geek]

The best complete test kit for home use is the CYA test in the Taylor K-2006 kit here which you can get at a good price here and this kit measures CYA down to 30 ppm. Or you can get the equally good TF100 test kit from tftestkits.com here which has 36% more volume of reagents so is equivalently priced and measures the CYA down to 20 ppm.

Or if you already have a good FAS-DPD chlorine test kit that also tests pH, TA, CH and you only need a CYA test, then you can the Taylor K-1721 here for measuring down to 30 ppm or the Taylor K-1720 here for measuring down to 20 ppm.

Richard