I use the same mixture as belegnole. I have a 100 ml Nalgene bottle in which I store the premix. Due to the way the metric system is designed 100 ml = 100 grams of water or at least close enough for our use. To dose a gallon of water, I use a 10 ml syringe with a non sharpened 4" needle to draw from the premix bottle. I draw 3.8 ml into the syringe and squirt that into the gallon of distilled water. rpavlis water made easy and convenient.

I use a 1 ml eyedropper, eyeballing the fourth squirt into a gallon and deeming it close enough (no need for undue precision).

Thanks to everyone who has contributed to this thread, it's helped me a lot. The concentrate for 1 gallon has been particularly helpful. I thought I'd share a couple recipes that I made.

Recipe #1: 5 gallon RO water mixed with the appropriately sized Third Wave Water espresso packet yielded: 187ppm/70 alkalinity.

Recipe #2: 3.8g potassium bicarbonate/distilled water concentrate mixed with 1 gallon of distilled water yielded: >17.1ppm/50 alkalinity.

Next test will be the RO and concentrate.

Both were done with the Hach test kit. Interestingly, a blind taste test for my family resulted in unanimous preference for recipe #2, wasn't even close. I preferred it to an earlier recipe I had made with sodium rather than potassium bicarbonate. I would like to reduce waste and hassle by using a refillable 5 gallon jug but I haven't seen
any distilled water dispensaries in my area, they're all RO.

I simply add 400 mg potassium bicarbonate into 1 gallon of distilled water.

No concentrate. It dissolves fine and seems to work well for me.

homeburrero wrote:^^^^^ that one also looks good.

Another popular approach for folks that start with 5 gallon jugs of distilled is to simply add 1.9 grams of potassium bicarbonate to the full container. (That gives you the full strength, 100 mg/L water.)

This would produce the final result and not the distilled concentrate correct? I'm looking to switch over to this method and was probably going to end up getting 5gal distilled jugs. Just wanted something simple without having to worry about concentrates.

Thanks!

ping279 wrote:This would produce the final result and not the distilled concentrate correct?

Correct. When using large containers like 5 gallons it's easiest to just weigh the powder on a scale with 0.1 gram resolution and dump it into the container of purified water. Even for 1 gallon that works well enough if you try to hit roughly .4 grams. (0.3 g would give you water with 79 mg/L and 0.5 g would give you 132 mg/L of potassium bicarb, which are equivalent to about 40 mg/L and 65 mg/L alkalinity as CaCO3 - close enough for our purposes.)

5 gal? I don't think I could feel my arms after shaking a 5gal bottle for 30secs.

I keep my jug on the floor and mess around with it holding the jug from the top to slosh the water. Afterwards I wait a day or two for the minerals to fully mix with the water.

I bought a milligram scale and a 1000 ml container. I just pour 100 mg of potassium bicarbonate into 1000 ml of distilled water and then put that into my machine. It can't get any simpler than that.

If taste is not an issue, is the rpavlis completely safe to the machine and is the recommended formula?

Is there any advantage using a formula that has both alkalinity/buffer and hardness (Mg)? Something like this:
https://jayarrcoffee.com/blogs/news/a-g ... king-soda/