What can I use in place of DiChlor?

[Smartjack]

So, in trying to get rid of a HUGE algae problem on this years opening, I have totally messed up my CYA. Over the 6 years I've had my pool, my CYA has been rising every year, and I never knew why until I found this site last weekend. This year, after putting in 20 gallons of liquid chlorine to shock the pool, I also turned my chlorinator up high, to keep "shock level" until the algae cleared. After 2 weeks, it hasn't cleared, and my chlorinator has dumped in 40 pounds of DiChlor in the last 2 weeks.

Now, my CYA is about 200, my FC is so high nobody can read it, and I am in the process of a drain to try and get things under control. But, I've searched the forums and pool school, and found that DiChlor is a culprit for continued raising of CYA. So, when I get things fixed this year, I want to stop that. So, hear is "finally" my question.

I have a Polaris G-1000 watermatic chlorinator. It says to use only DiChlor in it. I love this automatic chlorinator, as it monitors PH and FC level all the time, and adds accordingly. It holds 10 pounds of DiChlor at a time, and makes for easy, trouble-free work of adding Chlorine. But, now I don't want to use DiChlor any more. What else can I put in this unit, besides DiChlor? Or, will I need a new Chlorinator to get rid of using DiChlor? If I need a new one, are there good automatic chlorinators that use liquid chlorine, so my lazy you-know-what can just fill every few weeks like I do now?

 

[JoyfulNoise]

Unfortunately you can not use anything else with this unit. The only other granular source of chlorine is calcium hypochlorite and I'm pretty sure it was never intended to be used in this system because it creates solutions with water that are very high pH and calcium hardness.

There aren't many other options here unless you completely get rid of the Watermatic system. The only source of chlorine that adds nothing to your pool is liquid chlorine (sodium hypochlorite or bleach). Everything else adds something you do not want. In the realm of automated systems TFP endorses are the following -

1. Human beings (dump the bleach in yourself everyday)
2. Salt-water chlorine generators (chlorine is electrochemically generated from sodium chloride)
3. Stenner pump - a peristaltic pump that draws LC from a container and pumps it into your return line
4. The Liquidator - uses the pressure differential across your suction/return lines to passively add LC to your pool from a large container

We also do not recommend the use of automated chlorine monitoring (ORP control) as it is very flaky and hard to dial in using the recommended levels of stabilizer (CYA) that we advocate here on TFP. And you see the reason why - your system basically dumped every larger quantities of CYA into your pool. This is why we stress self-testing of water chemistry here. It is absolutely essential that the pool owner tests his own water regularly so as to avoid the issues. We recommend one of two test kits - either the TF-100 from tftestkits.net OR the Taylor K-2006. Both use the FAS-DPD chlorine titration test and both come with the reagents for accurately measuring CYA levels.

Good luck,
Matt

 

[pabeader]

All solid forms of chlorine add something to the water, that you don't want long term. You are right in thinking that liquid is the way to go. Most of us use either a SWG or bleach. There are devices that can do the liquid dosing for you. I don't have direct experience with them. But there are a number of folks that do, and I'm sure one of them will be along shortly.

I was too slow Joyful has you covered.

 

[pooldv]

You are in the right track. You have options but they do not include solid forms of chlorine lime pucks, powders or sticks.

Option 1 saltwater chlorine generator

Option 2 liquid chlorine dispenser
Stenner pumps and tanks or Liquidator are popular choices

Option 3 manually dose liquid chlorine/bleach daily or every other day

More here, Pool School - How to Chlorinate Your Pool

 

[Smartjack]

Then, why on earth do they sell automatic chlorinators that use DiChlor, or even sell DiChlor in the 50 pound buckets at Sam's club?

To me, this says DiChlor was invented as maybe a tool for shocking? Say you want to throw 8 pounds into a 27,000 gallon pool like mine as a shock, and you are okay with raising the CYA by 18 with that amount (used pool math). But, with that logic, why sell 50 pound tubs? Is this intended for people who completely drain a pool every year, or plan on a LOT of splash out, so you are replacing that water often?

 

[JoyfulNoise]

Precisely. Stabilized chlorine products only really work in an environment where there is a regular exchange of pool water with fresh water or where the swim seasons are short (3-4months) and the pool owner will drain a substantial amount of pool water during winter closing.

Trichlor tablet feeders have a similar disadvantage - 6ppm CYA for every 10ppm FC added. Plus, trichlor is more acidic than dichlor so it often causes TA consumption as well.

 

[Donldson]

The effects of CYA on chlorine have been documented for decades but remains largely unknown or ignored by the industry as a whole. As such most people don't care that trichlor tablets and dichlor powder adds CYA, to them tablets are just convenient and dichlor is a fast dissolving powder. I can't say that it is ignored because profit margins might be hurt, but I can't say that isn't a factor either.

Dichlor certainly has a use for someone that needs a quick hit of chlorine, CYA, and acid. But as such a combination product it is difficult for me to ever recommend it to someone who is not completely familiar with their chemistry and the effects it has on it. Unfortunately the industry has no such qualms selling stuff to anybody they can get to buy it, Sam's club included.

 

[Smartjack]

Lithium-Hypo!!!!!!!

So, I'm thinking about what I'm going to do, since I don't want to give up my automatic chlorination, but for reasons you all know, don't want to continue using DiChlor.

As I'm researching different automatic chlorinators, and SWG's, I'm also reading in pool school. And, I run across Lithium-Hypo. I see no reason why that would not fit into my g-1000, since it is granular. I will have to buy a small amount to make sure, but I think it may be promising. That will let me auto chlorinate without increasing my CYA. Now, I know that Lithium-Hypo is very expensive compared to all you guys who are using liquid chlorine. But, it is only about twice as expensive as the DiChlor I've been using for the last 8 years. Account for the fact I may use less as years go on due to the CYA build-up, or replacing water now that I know about CYA, it may not be twice as expensive. That extra cost each year my be about a wash on the cost of a SWG install, plus replacing a cell in 3 to 5 years.

If I was saying I was going from daily liquid chlorine to Lithium-Hypo, you can all say I'm nuts. But, compared to what I have now, this may be a good solution for me. Now the question remains on the size of the granules. I guess I will also need to research if the fumes can damage the parts like the solenoid (but the DiChlor also does a number on that), or if the sun will break down the Lithium-Hypo when it is sitting in the container for weeks.

 

[Donldson]

Whether you are nuts or not doesn't really matter, it is your money. I will point out that pound for pound lithium-hypo is about 2/3 as strong as dichlor, so you will need to use more. Specifically it takes 6.5 ounces of dichlor to raise your FC 1 ppm, compared to 10 ounces of lithium. So you will pay more and have to buy more as well. I can't answer the problems you posit in the last paragraph, but lithium hypo is pH neutral compared to dichlor being somewhat acidic so it might be better on the device overall.

That said, if you want to trial it please post up details of your experience here. As I don't know of anybody who has ever tried regular chlorinating with lithium-hypo it would be great to learn from your experience. Up until now I hadn't heard of someone chlorinating with dichlor either, but it looks like it went as well as I would have expected

 

[Smartjack]

That said, if you want to trial it please post up details of your experience here. As I don't know of anybody who has ever tried regular chlorinating with lithium-hypo it would be great to learn from your experience. Up until now I hadn't heard of someone chlorinating with dichlor either, but it looks like it went as well as I would have expected

Well, when a brand new pool owner tells the pool company he wants automatic chlorination, and they sell you a product designed to do that, you (I) don't ask questions. I assumed a chlorination system designed to use DiChlor, and sold by a major company like Polaris, was a good product, and I didn't consider anything else.

i will try this out, and post results. I ran a across a few others on this site that use, or at least did at one time, the same unit I have. And yes, they were posting about high CYA years ago. So, they may no longer have the same system as me.

 

[JoyfulNoise]

Well, when a brand new pool owner tells the pool company he wants automatic chlorination, and they sell you a product designed to do that, you (I) don't ask questions. I assumed a chlorination system designed to use DiChlor, and sold by a major company like Polaris, was a good product, and I didn't consider anything else.

i will try this out, and post results. I ran a across a few others on this site that use, or at least did at one time, the same unit I have. And yes, they were posting about high CYA years ago. So, they may no longer have the same system as me.

I think it's a pretty common sentiment for those of us that owned pools BEFORE discovering TFP that we all feel like - "if I had known then what I know now...." Many of us would have done things differently (in terms of either building a pool or buying a home with one).

That's one reason why I enjoy reading some of the build threads because it's nice to see people take ownership of the process and make the PBs work for them and not the other way around.

Please do let us know how the lithium hypo goes. It's not a very common way to chlorinate pools (it is used in hot tubs more frequently) so having the data point will be interesting.

 

[Smartjack]

So, I have yet another "brilliant" idea, beside the Lithium-Hydro.....

My current auto-chlorinator detects the FC level, and when it gets too low, it fires a solenoid to open a valve and drop DiChlor. The solenoid is held on for about 8 seconds. The DiClor drops into a water reservoir to dissolve, and then flow into the pool plumbing. I could keep all this in place, and just replace the DiChlor with bleach. Instead of having the sensor system fire a solenoid, I can have it fire a pump I can pick up for about $50. That pump can move 3 gallons per minute. That pump can then just pump the bleach into the reservoir the DiChlor went into, and then to the pool. The 8 second time will dump in a little less than half a gallon. I've never used bleach, but from what I've been reading on here, that would be about my daily amount. If it needed more, the sensor would dump in another half gallon at that time.

I would just need a container for the bleach, but I can find that by seeing what people with Liquidators are using. My existing system held about 10 pounds of DiChlor, which I would check and top off once a week. I'm guessing about a 10 gallon tank would let me do the same. This would switch me from DiChlor to bleach for under $100.