Question about combining SWG with trichlor for larger pools

[JoeSelf]

Ditto, good posting. Not your average Joe.

After draining half my pool for high CYA after it got to 150 (Pool Store Directions). I found TFP. I had been on the Pool Solutions Site before and just wasn't sure about it. TFP had clear & concise methods based on science. Yes, I was afraid at first that I would screw it up and ruin the pool. I was on here every day at lunch reading and learning. Dave and Chem Geek were really posting every day and they had so much knowledge to share. After that first summer, there was no going back.

Thanks to all.

 

[BasicTek]

I personally would never advise removing an inline chlorinator when switching to TFPC, unless the space was needed

Ya, that came from my SWG installer. I guess it would have been tricky to fit both in the current space but I would have found a way to do so in hind site even if I had to expand my space.

 

[TXHeat]

I'll weigh in since I'm relatively new to the TFP methods and came because of high CYA from pucks and that I could no longer keep chorine in the pool, although it took 3 years of constant pucks to get there.

After having been using bleach for the last several months, I probably won't ever go back to pucks as my regular method of chlorination. My water has been clear and clean without even a hint of algae that I was fighting before, but it has brought on a new set of problems. My pool tile has a milky film on it that I can't seem to get off regardless of what I do.....tried acid/water mix, CLR, etc. Also my flagstone coping stains easily from the pool water more so now than before. Guessing it's the added salt from the bleach or high calcium, which is another problem I've had since I started. It went from around 300-400 to 600-650 in a short period of time. And lastly my pH is hard to keep in the target range. In three years, I never added an ounce of acid. In the last three months, I've added almost three gallons.

All that said, I will continue to use TFP methods because so far, it's been beneficial, simpler and cheaper than before. But I'm also glad I have an inline chlorinator (baffles me when people say they wish they didn't have one) because I will use pucks either when away from my pool/home for a long enough time to warrant it OR when I need to add some CYA back into the pool. And if the problems persist that I'm experiencing now, I may at some point go to a combination of pucks/bleach to chlorinate. But I won't ever go back to just pucks/shock.

Just observations from a somewhat newbie.

 

[ant 83]

This is my proposition. Any time a pool need to raise CYA levels, slowly dissolving trichlor pucks is the most trouble free method to raise it. In ALL cases.

Saying that's confusing and complicated just doesn't hold water. It's what's done in the vast majority of new pools after all. Done without difficulty I might add.

I guess we'll have to agree to disagree.

 

[Donldson]

This is my proposition. Any time a pool need to raise CYA levels, slowly dissolving trichlor pucks is the most trouble free method to raise it. In ALL cases.

What if the pool is running a low pH and TA? How is adding a very strong acid the most "trouble free" method to raise the CYA?

What if the pool needs to raise the CYA by 30? How is taking a couple weeks to dissolve trichlor the most "trouble free" way to do it?

You said "In ALL cases" so you must believe that in both of those cases it is the most "trouble free" way to do those. So tell me how.

 

[ant 83]

If it's low on alk, add buffer. Just like any other time. Add 1.5 cups of baking soda per each puck to make them PH neutral. Powdered CYA would require buffer as well, as CYA is an acid. This isn't rocket science.

What if the pool needs to raise the CYA by 30? How is taking a couple weeks to dissolve trichlor the most "trouble free" way to do it?

It's convenient, because chlorine is being added constantly, making FC more consistent. Trichlor is more stable than bleach, not losing strength as fast. Again, more convenient, and also lower cost due to less chlorine being lost to the angels share.

It's easier to add pucks than hanging a sock. Perhaps I guess, I've never used powdered CYA. But from what I've read here on TFP, some folks have issues with the stuff getting trapped in their filter, so they gotta wait before they can test anyway.

 

[Donldson]

Your advice that something is better is "ALL cases" is based on zero experience?

Groovy. I think I'm done here.

 

[ant 83]

Noted that you comment about me, and not what I said.

I'm done here

suit yourself

 

[Catanzaro]

If it's low on alk, add buffer. Just like any other time. Add 1.5 cups of baking soda per each puck to make them PH neutral. Powdered CYA would require buffer as well, as CYA is an acid. This isn't rocket science.

Haphazardly throwing chemicals in a pool is not a wise idea. My friend's solution to his pool (good friend in which I helped him close his pool) each week throws baking soda in (1.5 lbs.) and uses 3" tablets in a floating chlorinator. He has no idea what CYA is and once I tested his water. Someone recommended that he add baking soda to combat the drop in PH from pucks. His PH was way under 7.2, had absolutely no CYA (why I do not know) and each year wakes up to a green swamp. When his pool was closed, streaks of algae everywhere. I did not even bother with trying to educate someone who is this far along and mentally set in his ways of taking care of his pool for a long time.

I have to agree with Donaldson here. One can not recommend what is right or wrong for anyone's pool. Everything is based on the primary principle here at TFP and that is testing your water with a quality test kit. Now, I do not even open my mouth when someone comes for advice. If and when they order and receive a test kit, is when I will make an effort. Until then, nothing. Thanks for your time.

Almost everything, that seasoned members alike recommend on the forum is based on experience. There are reasons why CYA hangs from a sock and is not placed in a skimmer basket and ran through the filter. There are reasons why 3" tablets are short term and not long term.

 

[BasicTek]

SWGs do not cause pH rise. pH rise in a SWG pool is caused by the TA being too high and the pH being too low.

At the correct TA and pH there is virtually no pH rise at all. Many SWG pools operate with no acid required all year.

Pretty much the only chemicals you need to add to a SWG pool are salt and cyanuric acid to offset salt and cyanuric acid lost to water loss other than evaporation.

If someone has high TA fill water and lots of evaporation, the constant refilling can increase TA high enough to cause pH rise.

In that case, tabs can be somewhat helpful because the chlorine in the tabs is acidic and lowers TA and pH. (The cyanuric acid in the tabs is actually cyanurate, which is a base and causes pH rise. The net effect is still acidic.)

Tabs are often misused and that’s our primary concern. Exclusive use of tabs is not practical for most pools.

The original purpose of this thread is due to the fact that with TA 50 and PH 7.8 my PH still continues to rise into the 8+ (and I've seen many other threads with people having that issue). I haven't added any fill water since refilling my pool to reduce CYA from 220 in June. So I know 1st hand, the negative result of exclusive puck usage and this thread was not meant to have anything to do with "exclusive puck usage" it seems to have been sidetracked.

Without pucks my pool would need CYA (5-10 ppm per month), I need to add acid 10-15 oz a month, occasionally some salt and possibly some Calcium to keep CSI exactly where I want it. Following TFP, pool math, and using my Taylor kits...

With pucks I can remove the requirement all together for acid and CYA while even adding a little salt. I've seen many people come to this forum and their SWG is undersized, so it makes sense that a method that can offset the need for acid, and CYA could also be helpful to supplement FC for SWG owners that are undersized.

It seem that the thought/suggestion of using pucks as a supplement gets confused with using pucks exclusively, or using pucks in "all" conditions which is not what I originally suggested or even close to the purpose of this thread. I'm new here but it was conveyed to me that TFP is about knowing what is in your water and what needs to be in your water, not "avoiding pucks for all" conditions which is where some get confused and what caused the somewhat off topic debate in this thread....

 

[ant 83]

with using pucks exclusively, or using pucks in "all" conditions which is not what I originally suggested or even close to the purpose of this thread.

For the record, "all conditions" is not what I said.

Any time a pool need to raise CYA levels

Is what I said.

And I stand by it.

The problem with this is that it's actually MORE convenient to do it this way, and there is the danger that folks will get complacent with testing and balancing as often as TFP method calls for, and they wont want to switch to bleach when CYA levels get to where they should be.

Also, for clarification, I DO recommend testing with TFP recommended test kits, and following the CYA/FC ratio, and maintaining PH at recommended levels, and tracking CSI with plaster pools.

 

[Swampwoman]

Ant, I'm curious. Do you actually have a pool?

Your signature says you have a 340 gallon hot tub. If you have a pool, please update your signature.
Thanks in advance!

With repect to your position, you are welcome to stand by it, but it will not form part of TFP protocol fr the reasons I and others have outlined.

In BasicTeks case, puck supplementation may make sense because he's already at a low TA with high ph, is experienced at the cya test, knows the methods to control, and lives in FL, where rainfall indeed can make cya replenishment more frequent

 

[ant 83]

I do not have a pool. Just a hot tub.

I think discussing me, and my experience, and my own personal credentials, makes for a much more tedious conversation than the pool chemistry and methods brought up by the original poster. But for the sake of argument I'll address the topic.

I do use trichlor in my hot tub to offset the ph rise caused by bleach (it's not ph neutral as mods repeatedly claim here), and from the buffer added with top off water from evaporation. This also keeps my CYA levels from dropping over time caused by oxidation and splash out. My CYA levels drop on average one point per day. It does not take long for the dreaded confusing and complicated "moving FC target" to get away from me out of range. It avalanches in that the lower CYA levels are relative to what I think they are, the higher the chlorine are and the faster what's left oxidizes.

Using trichlor as an acid keeps CYA levels consistent (actually slightly dropping over time) in conjunction with bleach as my primary chlorine source, is the method I am using at this time. I bust the puck up into smaller chunks, then grind up the smaller pieces into a powder with a mortar and pestle, then add about a tablespoon at a time to knock my PH back down.

I believe that the chemistry is similar enough to contribute to this thread.

it will not form part of TFP protocol fr the reasons I and others have outlined

How about this proposal......

In saltwater pools, it is recommended that during the swim season, one puck should be dissolved per week, per 15k gallons to prevent CYA loss over time. Periodic CYA tests should be done, and changes to the puck dissolving schedule made to keep CYA levels from changing away from desired target.

That doesn't sound all that complicated, does it?

Are we really going argue that folks don't know how to dissolve pucks, or get confused about what that does to their pool water? Or that it is easier to hang a sock every week or whatever..... Or that it is better to let CYA levels fall lower over time so that the hanging of sock is something that happens so few times over the year that it is less work than adding the puck every week or two or three or whatever.....?

Is having a FC target moving a good thing, or a bad thing?

I feel like ya'll are being deliberately and unnecessarily obtuse here.

And also, for the record, the trichlor still doesn't dissolve as well as dichlor, even after it is ground up into a fine powder. When my pucks are used up, I will go back to using dichlor, despite its higher CYA content, because it is easier to use. I do not advocate the use of trichlor in spas.

 

[Swampwoman]

That's interesting because I do use trichlor in my hot tub I use a Pentair floater that releases 1" pucks very slowly to maintain a baseline FC, use a few teaspoons of ph up to offset the acidity, bleach to oxidize, and dilute or change my water frequently to lower cya.

The reason I do this is highly personal - I knew a couple that died from legionella contracted in their son's hot tub. This way I am certain to never zero out for even a second. For me, this approach works in the dead cold of winter better than other options in a small but easy to change volume of water.

My pool, however, is 24,000 gallons. And I far prefer the convenience of adding exactly the amount of cya needed any time I drop more than 10 points. My cya reading changes within 24 hrs and then my FC is dialed in on the swg to maintain precisely the ratio I want. There's just no way on earth that throwing a few pucks in is anywhere near as convenient in practice. Why would I want to adjust my swg percentage or run time, which is pretty precise, to accommodate a puck? Why would I want to alternately spike my chlorine level with pucks when I only need a bit more cya?

In my scenario, and others like me, it would be the equivalent of adding a "salt and pepper" mix to a recipe that only needs salt

CYA is cheap and in my experience, using pool math, bulletproof. Pucks vary in cya content ad dissolve rate by size and sometimes by mfg. Some puck producers put copper in em. (Eg chlorox blue). You just get better control using single-agent products in large volumes of water. If I had swg on the hot tub, believe me, I'd do the same

But we can agree to disagree

 

[ant 83]

I knew a couple that died from legionella contracted in their son's hot tub.

Yikes. Sorry to hear about that. 3 people I knew have passed away over the weekend unexpectedly. Even though I wasn't particularly close, it's still very sad to hear about. Sincerest condolences to you, and the loss of your people.

I'll look into the Pentair floater. I used a regular floater for a brief time, but did't like the chlorine gas wafting off the top vent holes onto my cover. Does your floater sidestep that issue? Thanks for the tip.

I appreciate your comments/perspective about about your salt water pool. I ain't gonna tell your your doing it wrong.

I'm curious though, how often do you need to do your 10 point CYA correction? How often do you test for CYA?

I suppose my lack of experience with pure CYA is showing. It sounds like a hassle to me.

 

[Swampwoman]

Thanks.
I test monthly and I add a bit on average every 2-3 mos re cya/pool.

For the hot tub, The little Pentair 1" puck dispenser still gives off that trichlor smell I hate when I open the lid but it dissipates pretty quickly because I literally have the floater dialed down to about a 2 mm opening. I keep my tub at 104 at all times, hence the strong desire for that baseline FC residual. As the cya increases, I supplement with bleach to avoid psuedomas (hot tub itch) which can occur if the CYA is too high for the FC level.

 

[ant 83]

I add a bit on average every 2-3 mos re cya/pool.

If by "a bit" you mean 10 points, one puck per week looks close enough to me for government work. You couldn't dial that in? One third of one point per day is gonna throw your balance out of wack?

From where I sit, it's less "salt and pepper" and more 'turkey with gravy', if you know what I mean. You get all three with pucks. FC, CYA, and acid. So, turkey, gravy, AND stuffing right?

You'd have to fuss with it every week though. I'll concede that your way works good. How's that eh?