KCl Water softener

[fish_4_all]

I have found Potassium Chloride in my local, Home Depot being sold as water softener. I need Potassium as when I ordered my dry ferts the first time I got plenty of everything but K.

Is it okay to use the KCl water softener tablets as a source of K in my tanks? Is there anything specific to look for to make sure it is the right one to use?

[neilanh]

I don't think I would try it, personally. The K that we dose in our tanks is potassium sulfate. I'd recommend placing an order. aquariumfertilizers ships very quickly.

[jsoong]

I've heard of people using KCl to dose K <although their source is NoSalt>. I would think that it would be OK as long as the KCl is pure (you'd want something like "100% USP" on the label). The Cl- may be an issue. Adding that is like adding salt (NaCl), too much & it will kill your plants - so you'd need to worry about salt crept & Cl accumulation as you keep dosing & need to do large pwc to reset the tank periodically.

Personally I use KNO3 since my plants tend to suck up NO3 like crazy & it keep bottoming out. I get mine from a hydroponics supply place, but others have use KNO3 from the grocery store. <I think certain brand of stump remover is also pure KNO3.>

[Purrbox]

Look at the labeling, if it's pure KCl then you may be able to use it. If there are other additives I would avoid it.

[fish_4_all]

I would order it but it would only be the K2SO4 so the shipping would be more than the cost of the ferts. If I needed to make a whole order it would be worth it but I have enough CSM+B to last 5 years and enough KNO3 to last another 2.

I will have to see waht the additives are. Have not been able to get the store employees to tell me so will have to see if I can find it myself.

[JohnPaul]

Presuming the advertising on the package is correct, you need to ask yourself...do you REALLY want to soften your water? That's going to introduce a whole new set of (potential) problems into your tank, including the possibility of lowering the pH and/or subjecting your tank water to the possiibility of rapid pH swings. Plus the potential for other changes to your water chemistry.

It's your tank and your choice, but my gut sense tells me you're risking an aweful lot for the sake of saving a few bucks. I wouldn't recommend it.

[fish_4_all]

That's interesting because at one time Gregs sold Potassium Chloride as a fert option for Chloride. That and they still sell Calcium Chloride as one on the recommended sites for dry ferts. Shop online at AquariumFertilizer.com . Not sure why it would soften my water. Is there some kind of reaction that would lower my hardness? I am adding Calcium and Magnesium for my GH so not sure where it would be a problem.

[JohnPaul]

Well honestly I am pretty fuzzy on the details of how softness/hardness works in an aquarium. But I think a good rule of thumb when it comes to ANYTHING aquarium related (whether it's fish, other critters, plants, critters, chemicals, you name it), if you don't know what something is going to do to your tank, it's probably a bad idea to put it in unless you have assurances from someone you trust very much that it's going to do what you want it to do.

[Purrbox]

When dosed in the amounts necessary for providing potassium, KCl is not likely to soften the water much at all. It would be another matter altogether if it's being put into the water softener (much larger quantities). Still, the basic question is still whether or not it is pure KCl or has other additives.

[fish_4_all]

Okay, that makes more sense now. Sorry if I came across as Snide JohnPaul, was not my intent. Chemistry was not my strong point when it came to reactions and such. All I know is how to dose and to do regular 50% water changes to prevent levels from getting too high.

The odd thing is, I have returned to dosing EI in one tank that has had green water for what seems forever and it is finally clearing up. Go figure. I thought I was dosing too much and it turns out, at least in the case of my tank, that it was too little.