Switching from Trichlor tabs to Liquid Chlorine

[rexl23]

Hello, all.
We are new pool owners and have been handling our own chemicals for about two months now. Pool is only 4 months old.

We have read the articles here for pool school and introduction and have decided to follow the advice and switch to liquid chlorine.

We have the Pool Math app too which is a great help.

I test our pool at least 3 times a week with a Taylor 2006 kit and have the Water Guru that sends us daily tests (although they seem to run very slightly higher than the Taylor kit).

I took the tabs out of the in line chlorinator and we removed the floater the builder placed in the pool. We want to avoid the CYA climbing too high. We then tested the water before adding anything.

We then added the amount of liquid chlorine the pool math app stated and waited about 3 hours and tested again the same time the Waterguru is set to send a reading for comparison.

Here are our numbers from the Taylor kit and WaterGuru in parenthesis.
FC: 5.0 (4.8)
CC: 0.2
PH: 7.6 (7.7)
CYA: 50 (59)
TA: 80 (72)
CH: 360 (366)

The hardest thing we seem to battle with is the PH fluctuation. It's always in range but we add acid pretty regularly (once sometime twice a week). We are North Texas and it's been 100+ degrees for two weeks or more now so we do have to top of water about once a week.

My question is when switching from Trichlor to liquid chlorine is there anything special that I need to do? Will I be adding some everyday and need to increase my Taylor testing to everyday or is that overkill?

Sorry for the long post, but thank you in advance for the help. Trichlor tabs are so easy but I have read the warnings about the side effects. I don't want to mess our progress up by swapping to liquid.

 

[mgtfp]

Welcome to TFP, Rex!

You're doing great, really good start to the TFP method.

Would be great if you could fill in the header details and your signature with your pool details (hold phone landscape to see signatures). This will help people with your questions without asking back the same questions all the time.

Aim with your chlorine additions to reach the higher target range, and make sure FC never ever drops below min. If in doubt, run FC on the higher side. Anything up to SLAM is safe to swim, but even short excursions into below-min territory can be "rewarded" with algae.

In the beginning, you may want to test more frequently to understand your pool's chlorine demand, depending on sunshine, season and bather load. Once you have understood how your pool behaves, you can relax a bit with testing.

Without the acid from the Trichlor you now see an upwards drift in pH. pH tends to rise because of the dissolved CO2 outgassing which raises pH. Like a soda - once you open a can of coke the CO2 bubbles out, which doesn't only make your coke flat, but also taste even sweeter, because it is now less acidic, i.e. it has now higher pH. The higher the TA, the more CO2, the faster the pH rise.

The good news is that because you are not adding acid via pucks anymore, you don't need the high TA levels anymore that were required to stop your pH from crashing with Trichlor.

CO2 outgassing also happened while you were using pucks (even faster because of the higher required TA levels), but the pH rise was hidden by the acidic chlorination with Trichlor - even overcompensated, and you needed to raise TA regularly with baking soda to stop pH from crashing.

By managing pH in the higher sevens your pH rise should slow down over time. Once pH gets above 7.8 (like 8.0), add acid to get it down to maybe 7.6. Each acid addition brings down TA a bit, which slows down the pH rise.

Don't fight the TA drop by adding baking soda. Just don't let TA drop below 50. Only once that happens, add baking soda to bring it back to about 70.

Ideally you'll find an equilibrium with TA around 60-80 where pH is relatively stable around 7.8.

Because of TA added with fill water to replace evaporation losses, your TA might keep rising, requiring acid from time to time.

 

[mgtfp]

And long-term you may want to look into Salt Water Chlorine Generators. Bit of an upfront investment, but in the long run way cheaper than buying chlorine, especially at the current prices.

And so much more convenient. Priceless...

 

[JamesW]

Just get a SWG and make your life easier.

 

[rexl23]

Thank you all very much.
I was nervous about switching chlorine mediums.

Sounds like I am on the right track and just need to maintain it now and watch the numbers like I was doing anyways.

No special switch over techniques to worry about is a relief. Just seemed odd to be running with no tabs on the feeder. It's all we knew so far lol.

The SWG definitely sounds like something I will look into. It was never presented as an option to us by the builder and we didn't know to look into it at the time.

I think I have the signature and profile info complete too now.

Looking forward to learning a lot here and maybe being able to help out someone else eventually.

Thank you again.

 

[mgtfp]

Yep, can see signature now.

It might be a good idea to test CH and TA of your fill water, this will give us an idea about what the future will bring.

Your CH looks pretty good for a plaster pool, but if you have high CH fill water this may rise over time. Being in Texas, I assume you have high evaporation losses. And everytime you fill up the pool, more CH gets added that stays in the pool (only H2O evaporates, leaving dissolved solids behind).

In case of high CH fill water it would be a good idea to consider that early on, before scaling develops.

 

[JamesW]

2024 Annual Donation Campaign

Hi all, Thanks to the fervent support of the TFP community, we have met our $10,000 goal! We appreciate all the users in this thread hyping the campaign and sharing warm and fuzzy TFP anecdotes. Completion of this campaign reminds us that TFP is a resource that people can trust with their pool...

www.troublefreepool.com

 

[rexl23]

Yep, can see signature now.

It might be a good idea to test CH and TA of your fill water, this will give us an idea about what the future will bring.

Your CH looks pretty good for a plaster pool, but if you have high CH fill water this may rise over time. Being in Texas, I assume you have high evaporation losses. And everytime you fill up the pool, more CH gets added that stays in the pool (only H2O evaporates, leaving dissolved solids behind).

In case of high CH fill water it would be a good idea to consider that early on, before scaling develops.

Thank you. I will do that tomorrow. It never occured to me to test the fill alone. Makes sense to know what I am adding when I fill. I didn't test the fill water alone yet but I did test the pool again to see the changes today's heat caused with my change to liquid chlorine. These are the Taylor kit numbers. 9 hours after first tests with 100+ temps all day.

PH - 7.6
CC - 0.0
TA - 90
CH - 270
FC - 3.4 (added liquid chlorine per pool calculator app to bring it closer to the high end like you suggested)
CYA - 50

 

[rexl23]

Another quick question, if I am adding liquid chlorine daily and I am the only one who handles the pool chemicals at my home, what could I do when I go out of town for work? The inline chlorinator was used for Trichlor tablets so from what I read dropping calhypo tabs in that would be a bad idea now.

Could I use a new pool floater and drop Cal hypo tabs in it? Or is there a better solution? I've tried searching but can't seem to find it.

Thanks again!

 

[mknauss]

I've tried searching but can't seem to find it.

SaltWater Chlorine Generator. Stenner pump and tank to inject liquid chlorine.

You can try cal hypo tablets in a floater. They still dissolve pretty rapidly.

 

[rexl23]

SaltWater Chlorine Generator. Stenner pump and tank to inject liquid chlorine.

You can try cal hypo tablets in a floater. They still dissolve pretty rapidly.

I probably won't be able to do the SWG for awhile but it is definitely on the list now after everyone's suggestions. I wish the builder would have mentioned it. Hindsight.

I'm usually only gone for work 3 - 4 days so even if I can set up a cal hypo floater for my wife to drop in the pool half way through that to keep the chlorine up and algea at bay that would be good.

Is the inline chlorinator never going to be an option for anything but Trichlor now? Like no length of time is great enough to have it cleaned out of the Trichlor tablets residue for it to be safe? Our local pool store sells slow dissolve calhypo tabs is why I am asking.

 

[mknauss]

The trichlor thing is for, trichlor. Regardless if you have never put trichor in it, the Cal Hypo tablets will not work in it. They will dissolve very rapidly and they leave a gooey substance that will likely mess up the internal workings of the trichlor thing. They make Cal Hypo feeders for commercial pools.

Cal Hypo is one of the most dangerous pool chemicals you can store. Be ware of that.

Chemical Storage and Safety - Further Reading

www.troublefreepool.com

 

[rexl23]

Got it. Thank you for the clarification. I'll probably stay away from the calhypo all together unless some weird situation arises.

Maybe if I can keep CYA in line using the liquid chlorine while I am home I won't have an issue dropping a Trichlor tablets in the feeder just on the days I'm away then removing it.

Just trying to figure out the whole being away multiple days thing has me confused lol

 

[BDY]

+100 for SWG as you already have a variable pump. Marry the two for low cost, low maintenance running. Many with variable pump and SWG run low speed 24/7 at a fraction of the cost you would think ($15-20) a month, have no worry about vacation or lugging jugs and are very happy.

Your chlorine pool will develop salt over time as a byproduct so moving to a SWG pool isn’t really that big of a water step - more of an upfront fixed cost to reduce operating cost. Being in Texas you will have a much longer season than most so it makes even more sense!

Also, if no one has said it - because your pool is new and plaster you will have pH rise the first 12+ months anyway (like me - I’m using 8-10 oz of acid a day on a 4 month old 10k pool). The pressure of the curing plaster on the pH will lessen eventually…

 

[BDY]

SWG How It Works - Further Reading

www.troublefreepool.com

 

[reggiehammond]

As long as you're careful with your CYA levels, you can use a floater from time to time. You'll also learn your typical FC losses and can dose additional liquid prior to your travels (up to SLAM level perhaps.)

But - you're going to end up with a salt water chlorine generator. You should just do it now.

CircuPool RJ-30 PLUS Saltwater Chlorinator | Discount Salt Pool

www.discountsaltpool.com

This would be a good unit (the RJ 45 using $10 upgrade link from above link.) It'll make FC for you ~7-8 months of the year, enabling a much more hassle-free life. No more expense of jugs, no more time to go find liquid, etc. Just note that there are months of the year where Home Depot, Walmart, etc do not regularly stock liquid chlorine here in the area.

 

[BDY]

Salt Water Chlorine Generators

Salt Water Generators are designed to produce small amounts of chlorine continuously. This is perfect for day to day use and reduces work for the homeowner.

www.troublefreepool.com

 

[BDY]

Ps - the only time the SWG isn’t working is when end of life of cell, pool salinity is too low, or water temp below ~50F. But the first two you control and the cold temperature one you switch to liquid chlorine by that point. FC degrades minimally in cold water so a little liquid chlorine lasts you over the winter

 

[rexl23]

BDY and reggiehammond....thank you both for all the tips and the link. It sounds like I may just take on the SWG cost as soon as possible. Would definitely be less stressful in the long run.

The PH rise makes sense too. I use about a cup of acid a day. I was storing it and then getting it out and then storing and getting it out. Now it just sits ready to go.

 

[BDY]

If no one has said yet…

Make sure you store it outside - not near any metal. The bottles vent by design and the fumes are corrosive.

Also don’t store near chlorine - the two have a chemical reaction of fumes if mixed similar to mustard gas…