Simple (?) Water quality question

[mikewitt]

Hi all. I'm just in the process of getting into homebrewing, and in preparation I've been stocking up on equipment and reading as much as I can. However, I haven't seen much on this particular topic: analysis of RO water. Basically, everything I've read says that you should test your water, or find a water quality report, and if it's too hard, use RO or distilled water for brewing (of course, there are plenty of people who say that just about anything potable will work with some campden tablets).

Before I begin, I think my water is fine for brewing right now, and I think I'm a long way off from actually trying to get my water to a specific profile/chemistry. But this question has been burning at me for the last few weeks.

When I moved into our house, I ran an RO system to feed my fridge (which was a couple of months ago as we have extremely hard water around here, TDS ~200 PPM). So my plan is to just tee off of that water line and take about an hour to fill the brew kettle. In order to make sure that my RO filter is working, I got an inline TDS meter to make sure I replace the filters when necessary. Well, the water is so hard that I get a TDS reading of about 15-18ppm on the output of the RO filter. I think that's not unreasonable for a cheap RO filter off Amazon (and, as I said before, probably more than adequate to start with).

I noticed that if you're interested in looking at the composition of the water and interested in changing it, you just calculate your volume and how much salts you need to add. And 15-18ppm seems lower than most of the guidelines (by quite a bit)... So I was wondering if I should treat it the same as distilled water... Or if (when I decide to try my hand at tweaking the water chemistry) I should get some kind of test kit and actually test the RO water.

But, my more pressing concern is, with the TDS reading at 15-18ppm, will there be an appreciable amount of chlorine/chloramine left in the water?

 

[carluchi]

I'm not sure there would be any chlorine / chloramine left in the water after its ran through the RO filter. That is usually its main thing to trap / remove.

Does your water smell like chlorine after its filtered? If not and it tastes fine, then brew on. You can get into the weeds about salts and what not later.

When you do decide to step into the weeds, a water analysis would be where I start and then take it from there.

Good luck

 

[RPh_Guy]

IMO the residual ions are negligible. I don't think a report is needed.

 

[nrjones89]

I don't really mess around with my water too much and I just use tap water. We have really hard water, so I add a little calcium chloride when I am mashing to get a mash of about 5.5. I also add some powdered campden tab to remove chlorines as well as yeast nutrient and Irish moss. It's pretty good for most beer styles except stouts.

 

[mikewitt]

I'm not sure there would be any chlorine / chloramine left in the water after its ran through the RO filter. That is usually its main thing to trap / remove.

Does your water smell like chlorine after its filtered? If not and it tastes fine, then brew on. You can get into the weeds about salts and what not later.

When you do decide to step into the weeds, a water analysis would be where I start and then take it from there.

Good luck

Thanks! This seems to be the consensus, and more or less along my line of thought. I'll stick to my original plan of just using the water I have, and when I do decide to get down in the weeds of water chemistry then I'll get a kit to properly test my water and see what all is lurking in it.