Potassium water softner question

[pjhaddock]

My tap water is pretty good and I have always used it. The only constant issue I have with it is that it makes my Alk high. Straight out of the tap, the Alk is 2.11meq/l or 5.95dKH, when mixed with IO, its usually around or over 5meq/l and settles around 4.2meq/l or 11.65dKH. I get my water before it enters my water softner (not really sure why I have one since my water is not "hard", but I have always had one).

Here is my question, would I have a problem if I got the water, post-water softner? I use the potassium salt, not sodium. My GH and KH would both be 0 then, but the water would have potassium in it instead....Thanks for comments/suggestions!

Philip Haddock

 

[Randy Holmes-Farley]

In general I do not recommend tap water for reef aquaria for the reasons detailed here:

Tap Water in Reef Aquaria
http://www.advancedaquarist.com/issues/jan2004/chem.htm

Using that potassium chloride treated water for water changes may or may not drive up the potassium to undesirable levels, but I'd be even more concerned with constant top off to replace evaporation.

Can you use water from before the softener?

FWIW, I hadn't thought the softener would impact alkalinity, but perhaps it depends on the type of resin used.

 

[pjhaddock]

Yes the water that I use is tapped in before the water softner. The Alk comes out at 2.11meq/l and therefor makes the mixed Alk pretty high in relation to the calcium. I think the GH of my water is like 7 (trying to remember from my freshwater planted tank days). I have not tested but I was thinking that the softer would make the Kh 0 as well as the GH 0. TDS would obviously not be 0, but I dont have a way to test that.... THanks!

 

[Randy Holmes-Farley]

I don't generally expect water softeners to drop the alkalinity (KH), but I could be wrong on that. Certainly the whole point of a softener is to reduce GH (magnesium and calcium).

In any case, if you feel that you want to risk using tap water, I'd use it before the softener.