Cyanuric Acid - necessary evil?

[P00LNerd]

I'm running a 15k gallon pool (Radiant Metric semi-inground) with solar cover and heat pump heater, with a Frog Leap system, and having one heck of a time with ever-increasing cyanuric acid levels. It's to the point where I just ran the Frog Leap without a chlorine "torpedo" most of last season, finding it easier to manually dose liquid chlorine. Unfortunately, it appears there's no chlorine pack for this sanitizer, which does not contain cyanuric acid.

We changed out about 25% of the water in the pool this spring, and have been holding the chlorine at a nice 0.5 - 2.0 ppm, which is ideal for the Frog mineral pac systems. However, our CYA levels have already crept up beyond 50 ppm, to where the dealer is now telling me I should be pushing the chlorine higher, to keep the proper free chlorine / CYA ratio. Of course, that's a slippery slope, as turning up the chlorinator also means increasing CYA input to the pool, on the Frog system.

I suspect "get rid of that Frog system" is going to be somewhere in the answers to this post, but my dealer seems to love them, and I do like the idea of running lower chlorine levels they promote. I just don't understand why they put so much CYA in these things, and don't offer a low-CYA or even CYA-free version of the torpedo packs, for those of us having this problem. It appears I'm not the only one.

Two questions to start:

1. I'm told the only way to lower CYA is by water exchange, but I also see products online that claim to reduce or remove CYA. Do they work? How?
2. Would removing the solar cover reduce CYA? I've seen conflicting info on this. I thought solar cover (blue) = reduced need for chlorine = reduced CYA input from sanitizer, since the CYA is in the chlorine tablets.

The only other complicating factor is that the sanitizer is downstream of our heater, which runs variably according to weather, and whether we have the solar cover installed overnight. When the heater runs a lot, the chlorine (with CYA) levels spike up, due to heated water dissolving the tablets much more quickly than unheated water. The Frog will over-chlorinate the pool in this scenario, even with it's control knob dialed down to zero, unless you remove the chlorine torpedo or bypass the Frog completely.

Thanks!

 

[P00LNerd]

Oh... and I have considered just cutting open a Frog Torpedo and filling with my own CYA-free 1-inch chlorine tablets, if I can find them. But it appears most chlorine tablets are 'tri-chlor", which I believe contains CYA.

 

[Newdude]

keep the proper free chlorine / CYA ratio

You either have the appropriate FC/CYA ratio for sanitation, or you don't. There are no 2 ways around it. Err. There's *exactly* 2 ways. Sanitary / unsanitary.

I do like the idea of running lower chlorine levels they promote

They promote blatant lies. With already sanitary water, and daily FC added to keep it that way, your FC loss battle is with the sun. None of these alternative sanitizers do anything to reduce UV loss from the sun.

It may take less chlorine to kill the algae they gave you, but it does not lower UV demand in any regard. The irony being if you follow the manufacturers advice, you will have algae, then need their algae control product / device.

but I also see products online that claim to reduce or remove CYA. Do they work? How?

Most are enzymes which work in a lab, but not in the real world. There are several catalysts needed to make the process work, and it's just not found in your pool.

There are also newer pillow like things for the skimmers that are more or less soft Britta filters. They also don't work as advertised. They claim a 10ppm monthly reduction regardless of pool volume, the first red flag as that's 4X more in a 30k pool than a 7500 gallon pool. Then *if* they worked, it would still take months and months to reduce the cya from 150(?) or whatever the tab pool climbed to. But by the time anyone figures that out, their $50 is long gone.

Would removing the solar cover reduce CYA? I've seen conflicting info on this. I thought solar cover (blue) = reduced need for chlorine = reduced CYA input from sanitizer, since the CYA is in the chlorine tablets.

Solar covers would reduce the FC demand, by actually shielding the pool from the sun's UV, needing less pucks/tabs, adding less CYA with the daily FC.

But it appears most chlorine tablets are 'tri-chlor"

Most tabs are Trichlor. Dichlor (powdered shock) also adds CYA. CalHypo which is the other option jacks the calcium instead, so we recommend liquid chlorine which doesn't add anything else. (Except a little salt).

 

[Parac]

Oh... and I have considered just cutting open a Frog Torpedo and filling with my own CYA-free 1-inch chlorine tablets, if I can find them. But it appears most chlorine tablets are 'tri-chlor", which I believe contains CYA.

Absolutely do not do this. Mixing different types of chlorine is never a good idea. CYA free tablets would be cal-hypo which can cause an explosion when mixed with even trace amounts of trichlor left in the torpedo.

 

[P00LNerd]

You either have the appropriate FC/CYA ratio for sanitation, or you don't. There are no 2 ways around it. Err. There's *exactly* 2 ways. Sanitary / unsanitary.

Understood. But if CYA keeps climbing, then the FC requirement becomes high, and I suspect there are penalties for running high FC (eye irritation, corrosion, liner degradation, etc.). Right?

They promote blatant lies.

I had already suspected this.

Most are enzymes which work in a lab, but not in the real world. There are several catalysts needed to make the process work, and it's just not found in your pool.

Worth trying at all, or no? Trouble is, water exchange on a well is not a simple matter, and neither is getting a tanker truck out to our location. It's not impossible, but it's an expensive PITA.

Solar covers would reduce the FC demand, by actually shielding the pool from the sun's UV, needing less pucks/tabs, adding less CYA with the daily FC.

What I'm hearing is that what I was doing last year may be my best course of action:

1. Keep solar cover on when not in use, to minimize tri-chlor tab usage from Frog
2. Remove chlorine torpedo from Frog whenever chlorine starts to climb uncontrollably, which will also limit CYA
3. Manually dose liquid chlorine as needed, when CYA gets high

I also installed a Jandy bypass valve around the Frog, thinking I could throttle "below zero" by bypassing some or all of the water around the Frog sanitizer. Of course this means no "minerals" when bypassed, whatever that really is, versus leaving Frog in the loop and just removing chlorine torpedo.

 

[CreedenceTapes]

Chlorine tablets come in three varieties: (1) trichlor, (2) dichlor, and (3) cal-hypo. Before long, (1) and (2) overdose CYA, and (3) overdoses calcium. There is no tablet that's good for routine sanitizing, though you can get away with them when you go on vacation if your water has room for either the CYA or the calcium that tablets will add.

I just don't understand why they put so much CYA in these things, and don't offer a low-CYA or even CYA-free version of the torpedo packs, for those of us having this problem.

It's the nature of chlorine itself. Elemental chlorine is a gas. To use chlorine in solid form to sanitize a pool, it has to be in a compound that is solid. So with dichlor and trichlor, for example, excepting unintended impurities there is chlorine and CYA in every molecule that makes up a puck with no fillers. It's just the nature of the beast.

Compare it to table salt. You probably know that it's sodium chloride, but they don't make it by adding sodium and chlorine to a vat and stirring them up, and you can't get table salt without sodium in it.

 

[Donldson]

I suspect there are penalties for running high FC (eye irritation, corrosion, liner degradation, etc.). Right?

Nope. You're buying in to the Frog marketing. They create a demand and then fill it, which causes problems that they can also make sales solving. Quite convenient, right?

My pool had the Frog system when I got my house. The pool felt like your typical chlorine pool and had regular algae problems. Then I switched to TFPC. Now I get compliments about my "low chlorine system" while running 10-20x higher chlorine levels than I did with the Frog. It's all about following the FC/CYA Levels.

And those "minerals" are silver in the Frog, and copper in their algaecide. Interesting that they scare people of swimming in chlorinated water, but are perfectly fine swimming in water with high level of metals? Well, whatever generates the most profit, right?

 

[CreedenceTapes]

Understood. But if CYA keeps climbing, then the FC requirement becomes high, and I suspect there are penalties for running high FC (eye irritation, corrosion, liner degradation, etc.). Right?

The biggest problem is the time, effort, and expense of keeping your chlorine so high. Just as high CYA will prevent chlorine from killing the stuff you don't want growing in your pool, it will largely mitigate those other effects too.

Worth trying at all, or no?

No. I'd elaborate, but it's as simple as that.

What I'm hearing is that what I was doing last year may be my best course of action

Long term, the only practical ways to sanitize your pool are daily doses of liquid chlorine or a salt water chlorine generator.

 

[Newdude]

But if CYA keeps climbing, then the FC requirement becomes high, and I suspect there are penalties for running high FC (eye irritation, corrosion, liner degradation, etc.). Right?

The CYA buffers the active sanitizing agent of the chlorine (HOCL) so with more CYA, proportionately more FC is needed to sanitize at the same level. All lines on this chart are considered equal for sanitizing.

Worth trying at all, or no?

We've had a great many try unsuccessfully over almost 2 decades. If I had to guess, I'd say 10% saw some CYA loss but that may have been aided by outside factors as well such as leaks or rain dilution.

Trouble is, water exchange on a well is not a simple matter, and neither is getting a tanker truck out to our location. It's not impossible, but it's an expensive PITA.

Case and point that if these reducers worked, it would allieve everyone's issues with well water or crazy expensive fill water.

What I'm hearing is that what I was doing last year may be my best course of action:

Solar covers reduce UV loss and also evaporation which accounts for about 70% of your heat loss. The frog though adds copper/silver which will eventually stain the pool and swimmers. It will also be unsanitary if the manufacturers recommendations are followed.

So we recommend liquid chlorine to an appropriate level on the above chart, then also a solar cover for those who wish to lower FC demand or retain heat. They're a PITA though, so everyone has a love/hate with them. And I mean *everyone*.

In the northeast with a short season and about 4 ft of annual rainfall (most of a free water exchange), you can successfully alternate tabs, calhypo and liquid chlorine as the calcium or CYA becomes high. But reliable home testing is key to know where you are and what you can afford to raise besides FC.

As said above, never, ever mix different forms of chlorine unless it's in the pool with some mixing time between them. Once they hit the water it's all just chlorine but before that, say in a tab feeder or a storage bucket, explosions happen.

 

[CreedenceTapes]

Note that, if your pool gets substantial sunlight, it will very gradually lose CYA. My pool gets a ton of Florida sun, and I'm losing 10-15 ppm per month this time of year. I don't know if you could count on that in Pennsylvania, but if your pool gets good sun and your CYA is just a little out of range, you might able to let the sun cook off enough of it if you switch to liquid chlorine.

 

[P00LNerd]

Wow... thanks, guys! This has been super-helpful. I'll try to answer some points, below:

Nope. You're buying in to the Frog marketing. They create a demand and then fill it, which causes problems that they can also make sales solving. Quite convenient, right?

Marketing genius.

My pool had the Frog system when I got my house. The pool felt like your typical chlorine pool and had regular algae problems. Then I switched to TFPC. Now I get compliments about my "low chlorine system" while running 10-20x higher chlorine levels than I did with the Frog. It's all about following the FC/CYA Levels.

Okay, point me in the right direction, here. I suspect "TFPC" is for Trouble Free Pool Chlorination, but have no idea what this is. A new set of hardware.

Kinda bummed I put serious energy into re-plumbing and re-laying out my equipment pad this past winter, around the Frog system. It was a small investment in dollars, but a very substantial investment in time.

And those "minerals" are silver in the Frog, and copper in their algaecide. Interesting that they scare people of swimming in chlorinated water, but are perfectly fine swimming in water with high level of metals? Well, whatever generates the most profit, right?

Yahbut... aren't all of the algicide products we're pouring into our pools based on copper?

Long term, the only practical ways to sanitize your pool are daily doses of liquid chlorine or a salt water chlorine generator.

The engineer in me has my mind always going to the equipment first, then deciphering its usage. So point me in that direction, if you can. We're talking about replacing the Frog chlorinator with some type of liquid chlorine doser?

I hear about "salt water pools", and have been told by some that this requires special plumbing and equipment. I had asked about it when purchasing my pool and equipment, but my pool retailer told me that's just another method of generating chlorine, it's still a "chlorine" pool. Never dug into the subject beyond that, but I am interested.

The CYA buffers the active sanitizing agent of the chlorine (HOCL) so with more CYA, proportionately more FC is needed to sanitize at the same level. All lines on this chart are considered equal for sanitizing.

View attachment 581961

Thank you, this is useful. I assume all numbers are in PPM, and "slam level" is shock?

We've had a great many try unsuccessfully over almost 2 decades. If I had to guess, I'd say 10% saw some CYA loss but that may have been aided by outside factors as well such as leaks or rain dilution.

Solar covers reduce UV loss and also evaporation which accounts for about 70% of your heat loss. The frog though adds copper/silver which will eventually stain the pool and swimmers. It will also be unsanitary if the manufacturers recommendations are followed.

I guess this is why they have me adding a small amount of scale and stain remover every week. I do see some mild staining above the water line in the skimmer and on the stairs (white fiberglass) but it's not detectible elsewhere.

So we recommend liquid chlorine to an appropriate level on the above chart, then also a solar cover for those who wish to lower FC demand or retain heat. They're a PITA though, so everyone has a love/hate with them. And I mean *everyone*.

Yeah, I have a love/hate relationship with that cover, but it really does a great job at keeping expensive heater run time minimized, in our cooler climate.

I'm fine with liquid dosing chlorine, the basic math is pretty simple. But would love if there were some type of automatic liquid doser that can be dialed in roughly close to the average need, esp. for when I go on vacation, etc. That is one time when I appreciate the Frog.

In the northeast with a short season and about 4 ft of annual rainfall (most of a free water exchange), you can successfully alternate tabs, calhypo and liquid chlorine as the calcium or CYA becomes high. But reliable home testing is key to know where you are and what you can afford to raise besides FC.

I was going to argue that all of our rainfall is spring/fall, with very little in summer, when CYA levels tend to be highest. But a quick search on Google seems to refute that, with Weather Trends data showing us near 4.5 inches/month, June thru September. I tend to leave the cover off late June - early August, when it's too warm to run a solar cover, so evaporation also peaks then. In other words, maybe not as much chance to exchange water, as you might expect, and we're already past the late-June peak sun.

As said above, never, ever mix different forms of chlorine unless it's in the pool with some mixing time between them. Once they hit the water it's all just chlorine but before that, say in a tab feeder or a storage bucket, explosions happen.

Fun. I store all of my pool products in an outdoor poly chest, that sits on a dedicated concrete pad near the equipment. Sounds like I'd want a second one of those to keep chlorine products separated, if running different types throughout the season.

Note that, if your pool gets substantial sunlight, it will very gradually lose CYA. My pool gets a ton of Florida sun, and I'm losing 10-15 ppm per month this time of year. I don't know if you could count on that in Pennsylvania, but if your pool gets good sun and your CYA is just a little out of range, you might able to let the sun cook off enough of it if you switch to liquid chlorine.

Yeah, between latitude and the many hundreds of trees in my yard, I am sure I get less sun than you. The pool is in a clearing, so it gets a good few hours of solid mid-day sun June/July, but much less spring and fall. Our max solar altitude angle in late June is something like 73 degrees, it never gets quite fully overhead.

Of course, with a dark blue solar cover installed all but the few warmest weeks of each season (when heater is probably also running least = no heated water blasting thru tablets), we may see most CYA troubles spring/fall.

 

[Newdude]

Thank you, this is useful. I assume all numbers are in PPM, and "slam level" is shock?

For us, yes. Slam/shock FC is 40% of the CYA level. For the industry, shock is a verb that doesn't factor CYA, becoming a dump and pray situation.

In other words, maybe not as much chance to exchange water, as you might expect, and we're already past the late-June peak sun.

Some people don't cover their pools in the off season and plenty of us have mesh covers that let it in anyway.

aren't all of the algicide products we're pouring into our pools based on copper?

Polyquat 60 isn't. And we aren't using algecide here, bevause we don't need algae control. The industry is fixated on algae control and not the reason they need it. But without algae, they don't get to sell a chunk of their products, so you be the judge why they shun science in favor of algae control after the fact.

my pool retailer told me that's just another method of generating chlorine, it's still a "chlorine" pool. Never dug into the subject beyond that, but I am interested.

All pools are chlorine pools. Either you add it with liquid chlorine / pucks, or a SWG produces it for you from very low levels of salinity. (10% of seawater). Each jug of LC or puck adds salt, and many LC pools accumulate a good chunk of a 'salt pools' salinity without ever knowing it. Some are already there when they decide to switch.

SWGs are the bees knees. You'd have to pry it from our cold dead hands for the ridiculously overwhelming majority of users.

 

[Donldson]

Yahbut... aren't all of the algicide products we're pouring into our pools based on copper?

First, no, not all algaecides have copper.
Second, I do not use algaecide in my pool. I have not added any copper to my water since 2009.

And TFPC is Trouble-Free Pool Care. Pool Care Basics

 

[SJPoe]

I hear about "salt water pools", and have been told by some that this requires special plumbing and equipment. I had asked about it when purchasing my pool and equipment, but my pool retailer told me that's just another method of generating chlorine, it's still a "chlorine" pool. Never dug into the subject beyond that, but I am interested.

High school chemistry.

Salt = Sodium Chloride - NaCL

Add water + electricity, and according to the laws of magic, you produce hypochlorous acid and sodium hypochlorite (bleach)...which are what does the sanitizing, and they eventually bind back into the pool as Salt.
The net effect is you add electricity, you get Free Chlorine, and that kills the nasties.
If you use Liquid Bleach (Sodium Hypochlorite) you're basiclaly skipping the electric step, and then free chlorine is added and then combines to make salt in the pool again.

Hence, a more accurate position would be 'any chlorine sanitized pool, is a salty pool'.

The big plus is convenience (no lugging jugs), and long term cost savings (while the upfront is expensive, the actual cost per FC is way way lower).

Special equipment = a Salt Water Chlorine Generator - but other than that, you don't need anything special.

 

[CreedenceTapes]

The engineer in me has my mind always going to the equipment first, then deciphering its usage. So point me in that direction, if you can. We're talking about replacing the Frog chlorinator with some type of liquid chlorine doser?

This is the only reliable style that I'm aware of. There are a couple of automated dispensers on the market, but if you read the reviews, they get dinged badly for reliability and longevity. It takes me five minutes a day to test my FC and pH and add liquid chlorine. Once it's part of your routine, it's nothing. You should be out there daily checking on your equipment/baskets anyway.

I hear about "salt water pools", and have been told by some that this requires special plumbing and equipment. I had asked about it when purchasing my pool and equipment, but my pool retailer told me that's just another method of generating chlorine, it's still a "chlorine" pool. Never dug into the subject beyond that, but I am interested.

Chlorine is good. It's your friend. As with all things, the poison is in the dose. Swimming in pure bleach would be bad, but you're not going to do that.

On SWCGs, I'll second what @newdude said, but add that the plumbing changes needed for a SWCG aren't huge. If you're an engineer, or otherwise a capable DIYer, you could likely do it yourself. You should know that the cells on them don't last forever, and that replacing them is pricey. But for that expense, you gain the convenience of not having to deal with liquid chlorine. You still have to test regularly, though, and adjust chlorine production depending on season, bather load, etc.

You'll rarely ever talk to someone who regrets going to a SWCG. I'm in a small minority of people who can taste the low level of salt required to make them work, and it bothers me. I liken it to swimming in broth. So I'd just say make sure you've been in one before you convert your pool to SWCG. Odds are very good that it won't bother you the way it does the persnickety few.

 

[Mdragger88]

Ditch the frog today.
Begin manually dosing your pool with liquid according to the
FC/CYA Levels. Use
PoolMath to calculate amounts.
Get one of these Test Kits Compared on order asap.

If you don’t want to manually dose consider a salt water chlorine generator (rated for at least 2x’s your pool’s volume)
or a stenner type liquid chlorine doser to do so for you.
You will still need to properly manage your parameters.
See

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

 

[Newdude]

Have a read ;

SWG How It Works - Further Reading

www.troublefreepool.com

And some more

Pool Care Basics
FC/CYA Levels
SLAM Process


The proof :
How Clear is TFP Clear?

 

[CreedenceTapes]

Yahbut... aren't all of the algicide products we're pouring into our pools based on copper?

TFP-recommended levels of chlorine and CYA are thoroughly algaecidal. You won't have to worry about any other algaecides. Also, keeping copper out of your pool will keep your swimmers' hair from turning green.

 

[SJPoe]

Yahbut... aren't all of the algicide products we're pouring into our pools based on copper?

No need to use them in my pool so the formulation is kinda moot

 

[Newdude]

Kinda bummed I put serious energy into re-plumbing and re-laying out my equipment pad this past winter, around the Frog system. It was a small investment in dollars, but a very substantial investment in time

Let's touch on this too because it's the printer principle. Ever wonder why you can buy a brand new printer, with ink in it, at up to half the cost of just the replacement ink ? It's because they know they got you, so they take a big loss on the device, then charge you many times the actual cost for years of cartridges. *Exactly* like that.

They want their device at your house. Then they have a field day lightening your wallet.