Which chlorine & why?

[BillD]

With my 18 x 36, 23,000 gal pool, I have found that pucks of stabilized chlorine are the cheapest. For the season which runs mid May to mid September, I use one 8Kg pail which costs between $30 and $40 at Costco. I have not noticed a pH shift, although I rarely test anymore, as the routine I have developed over the last 20 years seems to work for the amount of use the pool gets. Basically one puck every other day, with the occasional bottle of bleach for a light shock. Some years I add copper sulphate from the drugstore aiming for 1ppm of copper. I have not added CYA since the second year, nor after the liner replace. Occasionally, I add baking soda to increase the TA. I try and stay as far from the pool store as I can.

[andrrewdamien]

I was wondering what folks are using to chlorinate their pools.

Please leave comments with reasons why you use the chlorine that you do.

I use trichlor granules and cal hypo. The trichlor for my stabilized chlorine and then cal hypo. Liquid chlorine always gets watered down where I am so it is an expensive alternative.

BilliBob

A little attempt from you part, using chlorine pills regularly can help you in keeping significant amount of your money and stay healthier as well. So using chlorine tablet is always a smart decision because it is easy and affective in use of any other form of chlorine or pool cleaning material.

[lightandspace]

whats the specific use of chlorine and bleach?

[Adolfsmith69]

Chlorine is a highly efficient disinfectant, and it is added to public water supplies to kill disease-causing bacteria that the water or its transport pipes might contain.

[GaryB0925]

After maintaining my pool using liquid chlorine for over 10 years, I recently switched to granular chlorine and/or quick dissolving shock and what a difference! The last few years I was having a hard time during the summer keeping my pool water clean and clear. I was also having a constant battle with algae. I switched about 8 months ago now, and I have never looked back. My pool is sparkling clean and the water has great clarity. My algae problems have all but gone away. I had one minor algae issue in the 8 month period and that was during a time where I got distracted from maintaining the pool as closely as I should. It was quickly resolved with a dose of granular chlorine and Natural Chemistry's PhosFree.

Liquid chlorine is mostly salt water with a low percentage of chlorine. Granular chlorine is fast dissolving and a much higher concentrate of chlorine. Thus your pool is sanitized much better with the granular. Further, you don't get the salt solids building up in your pool like you do with liquid chlorine. For me, it's been an eye opener. It's made keeping my water balanced much easier and my pool looks better as a result.

Granular chlorine over liquid chlorine for sure!

[chem geek]

You obviously were not using a sufficient amount of chlorine to get to a Free Chlorine (FC) level high enough for your Cyanuric Acid (CYA) level. There are tens of thousands of pool owners using chlorinating liquid or bleach with no problem if they maintain at least a minimum FC that is 7.5% of the CYA level (5% for SWG pools).

As for granular chlorine, it adds other chemicals in the following proportions:

For every 10 ppm Free Chlorine (FC) added by Trichlor, it also increases Cyanuric Acid (CYA) by 6 ppm.
For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm.
For every 10 ppm FC added by Cal-Hypo, it also increases Calcium Hardness (CH) by at least 7 ppm.

[czechmate]

I would just add one important fact. The difference in selecting between granular or the "pucks" of chlorine should be guided not by price or the strength. Rather the decision should always start by checking which one will keep your investment in a gunite pool out of the harms way. One raises CH, the other CYA. Even at high levels of CYA and CH you can juggle the very important CSI (that alerts you to a potential plaster damage), manipulating PH, CH and CYA. Remember water temperature plays very important role here also!!
(So difference between $1.80 for Calcium Hypochlorite or $2.00 for a Tri-chlor hardly makes difference. It is the $4000-6000.00 price for a new plaster and ton of headaches if not done properly.
Many damages to the plaster occur in the winter months, when pool water looks clear with good color and no algae sign. We than grow complacent and lazy to test.
In 2-3 months gunite surface can suffer enough pitting that will harbor algae in the spring. Like with anything else, consistency in testing and understanding the basic relation of PH,CYA,TA and CH will prevent us from serious drain of our hard earned money.

[scott46]

Similar question. We have an 85,000 gallon inground gunite pool. Have been using 3" tabs for years but the chlorinators keep clogging or having other issues. We have used four different tab chlorinators over the past 8 years or so. Considering switching to liquid. I would appreciate anyones comments on feasibility, costs, who sells liquid chlorinators, etc.

Thanks.

[Poolspotpro]

Use liquid chlorine for shocking(superchlorinating) and 3" tabs for maintaining. Shock when chlorine level gets low which you want to happen often to prevent a combined chlorine build-up. Maintain 1-3 tabs in a floater or chlorinator at all times.

[chem geek]

The following are chemical facts that are independent of concentration of product or of pool size:

For every 10 ppm Free Chlorine (FC) added by Trichlor, it also increases Cyanuric Acid (CYA) by 6 ppm.
For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm.
For every 10 ppm FC added by Cal-Hypo, it also increases Calcium Hardness (CH) by at least 7 ppm.

So if you had 2 ppm FC per day chlorine usage, the CYA would increase by 36 ppm per month if there were no water dilution. If you do not proportionately raise the FC as the CYA level rises to ensure that the FC is at least 7.5% of the CYA level, then algae can grow faster than chlorine can kill it. If your pool is low in algae nutrients (phosphates, nitrates), then a lower FC/CYA ratio will prevent algae growth, but chlorine alone will prevent algae regardless of nutrient level if never below the 7.5% minimum (for non-SWG pools; for saltwater chlorine generator pools, 5% is the minimum FC/CYA ratio).

One can learn much more about this and other subjects by reading Pool School and Certified Pool Operator (CPO) training -- What is not taught.

[Huckleberry]

I use granular chlorine since it is dust free and dissolves pretty fast.It can also be applied as shock for regular chlorination.

[GPN]

At home I use an Aqua Rite Chlorine Generator. This equipment does all the work for me. It was packaged with a chlorine solution already. With this I no longer need to change the chlorine of my pool frequently. For me, this pool equipment is wonderful!

I have a 30,000 Gallon Hayward saltwater pool with an Aqua Rite Chlorine Generator. I live in the Philippines and as you can well imagine, It is hot all year and the sun eats chlorine like Pac-Man. Even with my Generator set to Super Chlorinate (Shock setting) it is not enough to keep up with the chlorine demand. I keep 4 or 5 Gallons of Chlorine bleach on hand and add a gallon when the level drops. The main reason I use the regular bleach is the availability of pool supplies is very limited here in a small city.

[Denniswiseman]

At home I use an Aqua Rite Chlorine Generator. This equipment does all the work for me. It was packaged with a chlorine solution already. With this I no longer need to change the chlorine of my pool frequently. For me, this pool equipment is wonderful!

I have a 30,000 Gallon Hayward saltwater pool with an Aqua Rite Chlorine Generator. I live in the Philippines and as you can well imagine, It is hot all year and the sun eats chlorine like Pac-Man. Even with my Generator set to Super Chlorinate (Shock setting) it is not enough to keep up with the chlorine demand. I keep 4 or 5 Gallons of Chlorine bleach on hand and add a gallon when the level drops. The main reason I use the regular bleach is the availability of pool supplies is very limited here in a small city.

What you say makes the most sense, other products put additional chemicals (CYA) in your water making your chlorine ineffective and building up your calcium
For every 10 ppm Free Chlorine (FC) added by Trichlor, it also increases Cyanuric Acid (CYA) by 6 ppm.
For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm.
For every 10 ppm FC added by Cal-Hypo, it also increases Calcium Hardness (CH) by at least 7 ppm

When your SWCG packs up make sure you get one that is at least double (or larger) than the rated output requirement for your pool and isn't running 24/7 at 100%

[Teapot]

Do you have any CYA stabiliser in the water? Unless you buy stabilised salt you'll need to add it. Without it your chlorine will burn off in a couple of hours and your cell will not last

[wcoast]

I'm glad you posted this topic, as I've been wondering which one to use also.