Liquid chlorine & questionable test results

[downwind]

My test kit shows everything in my 25,000 gal vinyl linered pool, filtered w/a DE system right in the money. I primarily dose w/a half gallon of 6% liquid chlorine daily (buy it at Sam's in a 3 large-bottle pack totaling about 4 gallons for $7.79) with a 2# shock once a week of Ca Hypo & MPS alternately, and 10 oz of No Mor Problems mid week. This results in less than $50 a month for chemicals, $75 once a year for a Nature's 2 cartridge and water that is always crystal clear. On a whim, I took a sample to Leslie's & The Pool Warehouse just to confirm my results. Leslie's confirmed that everything was perfect, while The Pool Warehouse said my PH & alkanity were very high & phospates were through the roof at 1,000. Of course, they wanted to sell me a gallon of this & a gallon of that, etc.

Question: Anyone else have a similar experience with really different test results from various "free" water testing places?

Also, I think I can expect a gradual increase in PH with regular use of liquid chlorine, so would a periodic dose of acid be a good preventive strategy?

Thx,

 

[dmanb2b]

Welcome to TFP

I'm sure we can assist you in answering your questions, but when asking questions like you have above, you should be a little more specific. What does right on the money or perfect mean? Please post a full set of test results for FC (free chlorine), CC (Combined Chloramines), PH, TA (Total Alkalinity), CH (Calcium Hardness) and CYA (Cyanuric Acid...aka stabilizer/conditioner).

See my comments below in blue

My test kit shows everything in my 25,000 gal vinyl linered pool, filtered w/a DE system right in the moneyresults please.

I primarily dose w/a half gallon of 6% liquid chlorine daily (buy it at Sam's in a 3 large-bottle pack totaling about 4 gallons for $7.79) with a 2# shock once a week of Ca Hypo & MPS alternately, and 10 oz of No Mor Problems mid week. This results in less than $50 a month for chemicals, $75 once a year for a Nature's 2 cartridge and water that is always crystal clear.
IMHO, you wasting money on all these products except for the bleach, they are just not needed
On a whim, I took a sample to Leslie's & The Pool Warehouse just to confirm my results. Leslie's confirmed that everything was perfectresults please, while The Pool Warehouse said my PH & alkanity were very high & phospates were through the roof at 1,000.again results are need, but you need not worry about your phospahte levels if you are dillegent in maintaining your FC Of course, they wanted to sell me a gallon of this & a gallon of that, etc.

Question: Anyone else have a similar experience with really different test results from various "free" water testing places? Yes happens all the time, please specify what test kit you are using at home?

Also, I think I can expect a gradual increase in PH with regular use of liquid chlorine, so would a periodic dose of acid be a good preventive strategy?NO...although bleach is high in PH in it's bottled form, once it's done reacting with you pool water and killing bacteria/algae it has minimal effect on PH. Acid demand is usually driven by your pool surface type (n/a in your case with a vinyl liner), water features and Total alkalinity levels

Please take the time to read through pool school, where most of these concepts are described in detail.

Welcome and we look forward to helping you out

Thx,

 

[JasonLion]

Yes, there are dozens of stories of dramatically different test results from different pool stores on this site every year.

You definitely have some room to save even more money. There isn't any need for weekly shocking and if you keep everything balanced correctly there isn't any need for the No Mor Problems either.

 

[frustratedpoolmom]

Phosphates are algae food, but if you maintain your FC levels according to the CYA chart, the level is irrelevant.

Nature 2 is an unneccessary and expensive gimmick.
http://www.troublefreepool.com/alternative-sanitizers-and-chemical-free-pools-the-truth-t3025.html
Save yourself the $75.

By utilizing TFP's methods, you should be able to reduce your chem costs by half. $50 a month seems excessive to me. MPS is more suited for indoor pools and spas. Maintaining proper FC levels means rarely, if ever, having to shock - certainly not routinely.

 

[downwind]

Thanks a lot for the timely responses! From the info supplied, there's no need to take up any more of your valuable times in going into detail. Once I deplete the excess chemicals I have on hand, I will certainly modify my procedures taking all the recommendations into consideration.

One more question, though: one of the things I have on hand is about 40# of calhypo granular. It is over a year old and I am not seeing the chlorine level increase as it should when shocking after a rainstorm using the usual dosage. Since it is a year old, has it begun to deteriorate? And if I continue to use it up, I am thinking I would have to use twice the dosage to get the proper results, putting an excess of calcium into the pool. Right now, calcium hardness is running 220.

Thanks again.

 

[downwind]

WOW! The Pool School info is fantastic! Talking about chemistry, when using liquid chlorine (sodium hypochlorite) as the primary sanitizer, what is the concern about eventual salt buildup?

Thx.

 

[JasonLion]

All forms of chlorine add salt to the pool, as do most other pool chemicals, but not very quickly. Typically the pool will settle somewhere around 1000 ppm of salt (plus or minus) after you have been using chlorine for a very long time. Bleach/liquid chlorine adds more salt than the other forms of chlorine, but the difference is not significant. Since salt is added so slowly and there is always some water replacement, the level never gets all that high.

 

[chem geek]

In the more extreme case where one has a cartridge filter so no backwashing and assuming no splash-out or rain overflow, then with full sun and no pool cover one would probably have a daily chlorine usage of at least 2 ppm FC per day. Using chlorinating liquid or bleach would increase the salt level by 576 ppm in 6 months or over 1700 ppm in 3 seasons of use, again assuming no dilution of water. If one used other sources of chlorine, such as Trichlor, the salt buildup would be half as much, but one would also build up Cyanuric Acid (CYA) at a rate of over 100 ppm in 6 months.

The salt is rather innocuous until it gets to fairly high levels, but the CYA is already a problem at 100+ ppm. Also, if there is any water dilution, then on a percentage basis the salt level is more easily manageable. If there is 20% dilution over a season, then the salt level using chlorinating liquid or bleach will be at a steady-state at around 2580 ppm (about the level in saltwater chlorine generator pools) while with Trichlor the CYA would reach a steady-state at around 450 ppm. In other words, with reasonable dilution, it is fairly easy to manage the salt level, but very difficult to manage CYA. There is some slow breakdown of CYA, but it's not fast enough to make up for this effect if only stabilized chlorine is being used and the dilution is not substantial.