Copper Sulphate: Liquid vs Granular

[Malakov]

I'll begin by mentioning that through my reading here I understand that copper is not something that should be added to the pool (risk of stains/green hair). I am an employee at a local pool dealer looking for more insight as to the differences between copper sulphate algaecide in liquid and granular form. Another local pool company carries what is called "C-Pool", which I've determined to be copper sulphate in granular form, although I am unsure of the percentage (I believe ~4%). We carry two liquid algaecides that contain the same ingredient (Algae Free and Algae Master), with 1.7% and 3.3% copper sulphate respectively, both 1L bottles.

How do these compare to their granular counterpart in terms of potency and their likelihood to cause staining? Our company boycotts this "C-Pool" but sells the liquid counterpart despite their discouraging of C-Pool?

Thanks for any clarification, long time lurker.

 

[duraleigh]

The problem you may come up against is that no one here deals with copper so it may be difficult to get an answer.

 

[chiefwej]

Any form of copper added to a pool is bad. A granular form is a particularly horrible idea. Adding copper in a form that can settle to the bottom and immediately stain the pool, what could be worse. Well I guess you could just throw chunks of copper in.

 

[Patrick_B]

Welcome to the forum Malakov. Sorry I can't tell you how they compare. Most of us believe there is no substitute for Chlorine and don't want the risk of any copper in the pool at all. With proper chlorination, there will never be a need for copper based algaecide. In general, we tend to stay away from anything that has potentially bad side effects through short or long term usage. Additionally they tend to be very expensive products as well, so for me, it's not an option to consider.

 

[Donldson]

Welcome to TFP!

I'm not going to tell you what you already know, but since you are asking can I assume you have some sway in what is used and/or recommended? If so have you considered suggesting a PolyQuat algaecide? It is not quite as potent as copper based algaecides but will not run the same risks of staining or hair issues. It also has some sanitizing qualities which, while very much not a substitution for chlorine, could be used to help promote it's benefits over all copper based algaecides.

 

[chem geek]

Once the products are dissolved in water, the copper sulfate will be the same. Yes, the granular could cause more staining if not dissolved when added (i.e. if it settles to the bottom and dissolves in concentrated form to stain the bottom surface), but the differences between copper sulfate products will be more about what else they contain. Some products contain certain types of metal chelators/sequestrants that hold some of the copper to try and prevent staining, but if overdosed they can still cause staining. It is not clear that they work any better than other copper sulfate products.

C-Pool Mineral Treatment (also shown here) does not appear to have a chelator/sequestrant and yes, it seems to have 4% copper sulfate. The concentration of copper sulfate is not relevant except for pricing since you can always add more or less to get whatever concentration you want/need in the water.

 

[Malakov]

I appreciate all the information that has been shared; I'm looking to best equip myself to avoid the pool store pitfalls most customers are wary of.

Just out of curiosity, when these copper algaecides list a "trade secret" equating to <2%, would that likely be the chelating/sequestering agent?

 

[Malakov]

Welcome to TFP!

I'm not going to tell you what you already know, but since you are asking can I assume you have some sway in what is used and/or recommended? If so have you considered suggesting a PolyQuat algaecide? It is not quite as potent as copper based algaecides but will not run the same risks of staining or hair issues. It also has some sanitizing qualities which, while very much not a substitution for chlorine, could be used to help promote it's benefits over all copper based algaecides.

Our location does carry an algaecide that appears to be identical in nature to polyquat but is only 30%. I have always been hesitant to "push" anything besides that. I have little influence over what chemicals we supply but I can control what I recommend to customers.

 

[chem geek]

Just out of curiosity, when these copper algaecides list a "trade secret" equating to <2%, would that likely be the chelating/sequestering agent?

Yes, quite possibly that can be the case because they don't always have to be listed in an MSDS. Of course, it could always be something else, especially in combination products, but the "trade secret" ingredient won't be an algaecide itself since that is always listed (and is in the PAN Pesticide Database as well).