Opening Pool - Stabilized and Unstabilized Chlorine

[colin313]

Opening our pool for the summer this week. Can I use stabilized chlorine tablets first to get my CYA up to 30-50ppm in my automated chlorinator, and then use non stabilized chlorine tablets once the stabilized ones are dissolved in the chlorinator? Or will this be bad for the pool if it’s made up of unstabilized and stabilized chlorine?

 

[Lake Placid]

Do not mix chlorine tablets in your feeder. Trichlor and cal hypo can explode when mixed.

Once chorine is in the water it’s just chlorine and doesn’t matter.

Only use what has been previously used in the feeder. If you have used trichlor in the past in the feeder use it to build CYA but then transition to liquid in the pool once you’ve reached your cya requirement.

Sadly you won’t see enough CYA increase fast enough with pucks during limited use, so you might as well set your CYA with stabilizer and go straight to liquid.

Cal hypo pucks after trichlor will just raise your calcium hardness which is unnecessary in your pool. Do not put them in your feeder after trichlor. Ever.

 

[colin313]

Do not mix chlorine tablets in your feeder. Trichlor and cal hypo can explode when mixed.

Once chorine is in the water it’s just chlorine and doesn’t matter.

Only use what has been previously used in the feeder. If you have used trichlor in the past in the feeder use it to build CYA but then transition to liquid in the pool once you’ve reached your cya requirement.

Sadly you won’t see enough CYA increase fast enough with pucks during limited use, so you might as well set your CYA with stabilizer and go straight to liquid.

Cal hypo pucks after trichlor will just raise your calcium hardness which is unnecessary in your pool. Do not put them in your feeder after trichlor. Ever.

Thanks for the info. If trichlor tablets are fully dissolved and the chlorinator is empty, what happens if I add Cal Hypo pucks, specifically Poolife NST Prime Tablets?

 

[Lake Placid]

Thanks for the info. If trichlor tablets are fully dissolved and the chlorinator is empty, what happens if I add Cal Hypo pucks, specifically Poolife NST Prime Tablets?

You risk an explosion in the feeder. Period. The residuals from the tabs don’t fully dissolve in the venturies and other nooks and crannies. You may think they are dissolved but they are not. I’ve had a long term friend/cohort that inadvertently mixed them on the advice of an ignorant homeowner who advised him it was always a trichlor feeder (but HO used cal hypo). It created a pipe bomb and once the lid blew off the chlorinator the siding of the house caught on fire. DON’T MIX THEM. DON’T PASS GO. DON’T COLLECT $200……DON’T.

 

[Mdragger88]

Opening our pool for the summer this week. Can I use stabilized chlorine tablets first to get my CYA up to 30-50ppm in my automated chlorinator, and then use non stabilized chlorine tablets once the stabilized ones are dissolved in the chlorinator? Or will this be bad for the pool if it’s made up of unstabilized and stabilized chlorine?

Each type of chlorine must have its own dedicated feeder.
Cal hypo & trichlor must never mix because they can explode if even traces are left behind.
whichever type of chlorine you have been using in your feeder is the only one you can put in there.
It is fine to use trichlor (stabilized chlorine tablets) if you need a little cya.
*Note that they are also acidic and will lower ph & ta.
Use PoolMath effects of adding to see each 8oz tablet’s effects on your chemistry.

Also know that Cal hypo - although unstabilized- adds calcium- too much calcium can cause scaling. The only way to lower the calcium in your pool is to exchange water.
We recommend using liquid chlorine or a salt water chlorine generator for daily chlorination.

How to Chlorinate Your Pool

Before chlorinating your pool, you should know these simple tips. Learn the best way to add chlorine to your pool.

www.google.com

 

[Lake Placid]

Opening our pool for the summer this week. Can I use stabilized chlorine tablets first to get my CYA up to 30-50ppm in my automated chlorinator, and then use non stabilized chlorine tablets once the stabilized ones are dissolved in the chlorinator? Or will this be bad for the pool if it’s made up of unstabilized and stabilized chlorine?

As advised in your thread here Opening Pool - Stabilized and Unstabilized Chlorine DO NOT!

 

[colin313]

You risk an explosion in the feeder. Period. The residuals from the tabs don’t fully dissolve in the venturies and other nooks and crannies. You may think they are dissolved but they are not. I’ve had a long term friend/cohort that inadvertently mixed them on the advice of an ignorant homeowner who advised him it was always a trichlor feeder (but HO used cal hypo). It created a pipe bomb and once the lid blew off the chlorinator the siding of the house caught on fire. DON’T MIX THEM. DON’T PASS GO. DON’T COLLECT $200……DON’T.

Sheesh I dodged a major bullet thank you! What about if I continue to use tricolor in the automated chlorinator but keep it at the lowest setting, and then put cal-hypo shock directly into the pool on a bi-weekly basis. Do you think this is a safe option to try and maintain reasonable CYA levels?

 

[Lake Placid]

Sheesh I dodged a major bullet thank you! What about if I continue to use tricolor in the automated chlorinator but keep it at the lowest setting, and then put cal-hypo shock directly into the pool on a bi-weekly basis. Do you think this is a safe option to try and maintain reasonable CYA levels?

From a safety perspective it won’t hurt anything. Once mixed in the water they are both chlorine. I believe regardless of the setting of a trichlor feeder, long term use will lead to unmanageable CYA levels. How fast you get there is a guess, but test frequently to monitor both your cya and your FC so you can 1. Increase FC levels to the proper ratio and 2. Discontinue trichlor use when you get to your target CYA.

 

[thefloatqueen]

You risk an explosion in the feeder. Period. The residuals from the tabs don’t fully dissolve in the venturies and other nooks and crannies. You may think they are dissolved but they are not. I’ve had a long term friend/cohort that inadvertently mixed them on the advice of an ignorant homeowner who advised him it was always a trichlor feeder (but HO used cal hypo). It created a pipe bomb and once the lid blew off the chlorinator the siding of the house caught on fire. DON’T MIX THEM. DON’T PASS GO. DON’T COLLECT $200……DON’T.

There is a YouTube video of an explosion from a trichlor x cal-hypo mishap. I’ll have to look for it lol. Crazy stuff!

 

[colin313]

From a safety perspective it won’t hurt anything. Once mixed in the water they are both chlorine. I believe regardless of the setting of a trichlor feeder, long term use will lead to unmanageable CYA levels. How fast you get there is a guess, but test frequently to monitor both your cya and your FC so you can 1. Increase FC levels to the proper ratio and 2. Discontinue trichlor use when you get to your target CYA.

Once I get to the target CYA, would it be ok to turn off the automatic chlorinator and then stick cal hypo tablets in the skimmer baskets? I’ve read you should never stick trichlor tablets in the skimmers, but cal hypo tablets aren’t a problem. Just want your thoughts

 

[colin313]

There is a YouTube video of an explosion from a trichlor x cal-hypo mishap. I’ll have to look for it lol. Crazy stuff!

 

[Lake Placid]

Once I get to the target CYA, would it be ok to turn off the automatic chlorinator and then stick cal hypo tablets in the skimmer baskets? I’ve read you should never stick trichlor tablets in the skimmers, but cal hypo tablets aren’t a problem. Just want your thoughts

If you want to use the cal hypo pickup dedicated floaters for them. Don’t put them in your skimmer baskets, you will destroy your equipment. Long term use of cal hypo will raise your calcium hardness levels over time - which you really only need a minimal amount with a vinyl lined pool. Eventually like cya you can only remove the hardness through draining or dilution.

 

[Lake Placid]

Well are her dishes now technically sanitized?

 

[thefloatqueen]

YEP! That’s the one lol

 

[colin313]

Do not mix chlorine tablets in your feeder. Trichlor and cal hypo can explode when mixed.

Once chorine is in the water it’s just chlorine and doesn’t matter.

Only use what has been previously used in the feeder. If you have used trichlor in the past in the feeder use it to build CYA but then transition to liquid in the pool once you’ve reached your cya requirement.

Sadly you won’t see enough CYA increase fast enough with pucks during limited use, so you might as well set your CYA with stabilizer and go straight to liquid.

Cal hypo pucks after trichlor will just raise your calcium hardness which is unnecessary in your pool. Do not put them in your feeder after trichlor. Ever.

Pool is now opened and CYA is already high. Whats your thoughts on this process. Turn off the automatic chlorinator and start using Bioguard Chlorinating liquid weekly, and then my cal-hypo granular shock bi weekly. Test levels weekly and turn on automatic chlorinator with stabilized chlorine as needed.

 

[Lake Placid]

Your option is to move to liquid chlorine, and probably partial water exchange/dilution to reduce cya. That’s speculation however without reliable test data. Post results of your water testing from a reliable test kit so advice can be tailored to what’s actually happening in your pool and not theoretical information.

 

[colin313]

Your option is to move to liquid chlorine, and probably partial water exchange/dilution to reduce cya. That’s speculation however without reliable test data. Post results of your water testing from a reliable test kit so advice can be tailored to what’s actually happening in your pool and not theoretical information.

I went and tested at the pool store and it shows my CYA level is 106 and that’s within range of 30-200ppm per the Bioguard test. I’m wondering why everywhere else on the internet says CYA should be 30-50ppm.

 

[rack04]

I went and tested at the pool store and it shows my CYA level is 106 and that’s within range of 30-200ppm per the Bioguard test. I’m wondering why everywhere else on the internet says CYA should be 30-50ppm.

This article does a good job "dumbing" down the reason why FC/CYA is so important. Using your pool store results, which shouldn't be trusted, your range of FC would be 8 ppm - 14 ppm and if you ever needed to SLAM you would need to increase and hold that at 42 ppm. It would take roughly 8 gallons of 10% liquid chlorine to raise from 14 ppm to 42 ppm.

2.0 to 4.0 Free Chlorine May Not Work • Pool Chemistry Training Institute

The PHTA Guideline for residential pools (ANSI/APSP-5 2011) states that the free chlorine level should be between 2.0 and 4.0 ppm. Many health codes have

poolchemistrytraininginstitute.com

Primarily this.

If you have 50 ppm of CYA then you need 3.75 ppm Free chlorine minimum (50 × 0.075 = 3.75). If you have 100 ppm CYA then you need 7.5 ppm Free Chlorine (100 × 0.075 = 7.5 ppm). However, according to US EPA Guidelines, swimmers should not enter the water when free chlorine is more than 4.0 ppm. Therefore, the absolute maximum amount of CYA in residential pool water should be 50 ppm (50 × 0.075 = 3.75 ppm) to keep the free chlorine level below the EPA recommendation. However, if using borate at 50 ppm, the required free chlorine level is 5% and you could therefore have 80 ppm CYA because 5% of 80 ppm is 4.0 ppm.

With this qualification on the EPA recommendation.

The EPA guideline for chlorine exposure is based on exposure to 4.0 ppm free chlorine when there is no CYA. EPA never considered the fact that 97.2% of the chlorine is bound to CYA at pH 7.5, 30 ppm CYA and 2.0 ppm free chlorine, or that 98.35% of the chlorine in the water is bound to CYA at pH 7.5, 30 ppm CYA and 4.0 ppm free chlorine. So swimmer exposure to chlorine when using 30 ppm or more of CYA is only 1.5 to 2.8% of the free chlorine level in the water. For example, at 4.0 ppm free chlorine, swimmers are exposed to only 0.11 ppm chlorine (4.0 × 0.028= 0.112). If there is 4.0 ppm of free chlorine with no CYA, swimmers are exposed to the whole 4.0 ppm. CYA keeps exposure to chlorine low. If using borate at 50 ppm, the free chlorine requirement is lowered to 5%. So you can have up to 80 ppm CYA because 5% of 80 is 4.0 ppm.

 

[Newdude]

. I’m wondering why everywhere else on the internet says CYA should be 30-50ppm

The industry reccomendations shun science. Plain and simple. They treat CYA and FC as 2 independent values, which instead have a relationship. Everything else online just regurgitates the industry way.

Please read : FC/CYA Levels

 

[Lake Placid]

I went and tested at the pool store and it shows my CYA level is 106 and that’s within range of 30-200ppm per the Bioguard test. I’m wondering why everywhere else on the internet says CYA should be 30-50ppm.

The industry also uses stupid terms like “chlorine lock” which is complete rubbish and recommends draining and refilling as the cure because by some mystery only known to those in the industry chlorine goes to chemistry jail and becomes ineffective until you drain and refill.

It’s a poor excuse for the reality the industry doesn’t want to address….CYA overdose is real. Trichlor pucks are convenient, (profitable for the industry) and a simple and easy sell and the average homeowner doesn’t want the inconvenience of jug lugging and actually managing their water with a few simple chemicals….so why not buy the simple pill…ehhhhhr…….puck…. aka Trichlor.

The science proves you can manage a CYA of 500 if you want to by maintaining the appropriate FC ratio for that level of CYA, however that effort would be too expensive to perform correctly and unnecessarily futile. Simplicity and science proves 1 thing - add only what you need, only in the amounts necessary and you can have a clear and sanitary pool. The industry tends towards being a monolith and selling a quick fix because it’s easy and profitable…and homeowners are complicit by willingly not educating themselves and wanting to spend the time to understand what they are doing…..This relationship is great until it ceases being easy for the consumer, and their pool is always green…and then it’s chlorine lock and the easiest answer is drain and refill.