Calcium Chloride Concentrations

[JasonLion]

Off topic side conversation split off of this topic.

Welcome to TFP!

Calcium chloride comes in two forms: calcium chloride and calcium chloride dihydrate, calcium chloride is about 35% more potent. Both products might be using either form. You can usually tell by reading the label, but sometimes they obscure which form they are using. Other than that there isn't any difference.

 

[oldcarkook]

Re: Calcium Chloride Vs. Calcium Hardness Increaser

Well, with all due respect that answer is not correct. My business of the past 40 years is calcium chloride.

Calcium chloride is commercially available in a variety of forms and Calcium Chloride (CaCl2) concentrations:
Commercial dry Calcium Chloride forms are: granular, flake, and pellet or spherical.
Commercial cry Calcium Chloride Concentrations are 74%, 77% (dihydrate), 83-85%, 88-90%, and 94-96% (anhydrous).

For the most part, the flake calcium chloride is typically dihydrate form of either 77% or 83-85% concentration, and pellet is typically 77%, 88-90%, or 94-96% CaCl2. In all cases the balance of these CaCl2 concentration is mostly water and some levels of NaCl (sodium Chloride) and other metallic chlorides in minor amounts.

The pool chemical companies purchase these various forms of calcium chloride and repackage and relabel them under a variety of names but calcium hardness increaser is pretty standard. I am not aware of any other calcium forms currently being promoted as calcium hardness increasers other than calcium chloride.

Some forms of calcium chloride, the 83-85% flake and the 88-90% pellet are from OxyChem's Ludington MI production facility and have higher levels of Bromine in them and can jinx some brominated pool systems if applied in significant quantities. A manageable problem, but one which you should be aware of.

So the key to understanding what you're buying SHOULD be disclosed in the labeling, but not necessarily always. If you purchase 50 lb. bags of calcium chloride (any form) locally, be sure to keep it in a TIGHTLY sealed container when you have used whatever portion you need. It is an intensely hygroscopic product which wants water constantly and will draw it from the air if left open in a bag and exposed to atmosphere. You can turn a 50 lb. bag into a 75 lb. hard slimy block in a relatively short period of time if you do not keep it sealed. This is why most pool chemical suppliers put it in a rigid resealable package. If you have any screw top plastic pails from chlorine tabs or other pool chemicals, best to put unused calcium chloride in there.

 

[JasonLion]

Re: Calcium Chloride Vs. Calcium Hardness Increaser

oldcarkook, welcome to TFP!

with all due respect that answer is not correct

What, if anything, do you actually disagree with? You provided far more detail than I did, most of which is information overload for the average pool owner, but otherwise seem to agree with everything I said. There are two forms (anhydrous & dihydrate), which differ in their useful calcium concentration per unit weight. I simplified things by leaving out the mixtures of the two forms, but that doesn't make any real difference.

 

[oldcarkook]

Re: Calcium Chloride Vs. Calcium Hardness Increaser

oldcarkook, welcome to TFP!

with all due respect that answer is not correct

What, if anything, do you actually disagree with? You provided far more detail than I did, most of which is information overload for the average pool owner, but otherwise seem to agree with everything I said. There are two forms (anhydrous & dihydrate), which differ in their useful calcium concentration per unit weight. I simplified things by leaving out the mixtures of the two forms, but that doesn't make any real difference.

This statement:

Calcium chloride comes in two forms: calcium chloride and calcium chloride dihydrate, calcium chloride is about 35% more potent.

Calcium chloride dihydrate is 77% CaCl2. 77% x 1.35 (35% more potent) would make the concentration 104% CaCl2.

I think you meant that dihydrate contains about 20% less CaCl2 than anhydrous, however it is virtually impossible to know the concentration of repackaged material unless it is noted on the label; a caution which I provided in my response.

I'm not looking to open a debate, I'm only trying to answer the guy's question and if this is not allowed, I can move along. As this product and it's chemistry is what I do for a living, I felt qualified to answer the question.

If your reader just assumes 35% more horsepower based on your response, and uses either concentration with that premise, his numbers are going to be out. If he is the unfortunate recipient of over-saturating the Langlier index, he's going to have a larger problem than he wants. http://www.pested.msu.edu/Resources/bul ... 1chap6.pdf As I'm sure many already know, once you over-saturate the Langlier index on calcium hardness, the only practical and quick remedy is to dump the water and start over which is an unattractive option for most if not all of us. You can chase this problem for weeks and never get it balanced before deciding to pull the plug on the bottom drain and starting over.

 

[Isaac-1]

Re: Calcium Chloride Vs. Calcium Hardness Increaser

Oldcarkook, Welcome to the board, hang around it is a great place.

Jason, In all fairness this question was posted in the Chemistry 201 section, which does tend to go into more depth than questions asked in the getting started, or testing and balancing sections.

To sum up all this for the OP, it seems that they can be the same thing, but strength will vary by about 25% or so depending on the brand and source, so use caution and don't overdose. Note the word of caution above if you use bromine.

Ike

 

[CaOCl2]

Re: Calcium Chloride Vs. Calcium Hardness Increaser

I don't think that's a fair editing job at all.

User oldcarkook's answer was very informative, having spent years in that industry he had the authoritive answer. His response, and the exchanges that followed, in no way went against any forum rules.

 

[JasonLion]

This entire conversation is off topic for the original post, which was about using deicer instead of hardness increaser, so it has been moved.

 

[duraleigh]

I don't think that's a fair editing job at all.

User oldcarkook's answer was very informative

I disagree. OP wanted to know the difference in the two products and JasonLion provided that answer.....simple.

I haul folks around in airplanes but, in thirty plus years, I have never had a passenger interested in the N1 or N2 rotational speeds of the turbines.....they want to know how long it will take to get there and if it will be bumpy.

People that are involved in the pool industry often mistakenly think that TFP is for them to discuss highly technical issues that have little to no influence on the majority of pool owners....it is not.

If you wish to discuss those technical issues, then the Deep End forum is the place. The vast majority of members on the forum want to keep their pools looking good, sanitary and go swimming.

Besides being a bit rude, (which will always get attention on this forum) oldcarkook's response got too far off topic and so wasn't edited but split off to start another discussion that someone might be interested in.