jgood wrote:Rereading the thread I did notice that it was mentioned that one could (should) use a more dilute version for dark roasts - in this case 19 grams of the concentrate. Is this correct?

Dr Pavlis said that he sometimes preferred the taste of dark roast brews using his recipe at half strength. That would give you an alkalinity of only 25 mg/L (CaCO3 equivalent) which is below the oft recommended 40 mg/L, but should be fine here because the rpavlis water is completely free of corrosive ions like chloride.

I mean, folks can do whatever works for them, but I cannot for the life of me figure out why people just don't throw 100 mg of potassium bicarbonate into 1 L of distilled water and be done with it. A good mg scale is inexpensive and readily available on Amazon. And it's super easy to measure 1 L (1000 cc) of water with good precision and accuracy. I just can't wrap my head around why people are jumping through extra hoops by messing around with concentrates. Maybe there's some benefit that outweighs the pure ease and simplicity of doing it directly?

IF I had a milligram scale THEN I would do what you do. But I am frugal (i.e. cheap) and have the <$20 recommended scale from Amazon that does not measure to milligram. Hence I use concentrate which I then add to 3.78L (1 gallon of distilled water). I test the water with cheap TDS meter and values are in ballpark of 100mg potassium bicarbonate per litre distilled water (and chemistry confirmed by "homeburrero" on prior water thread post).

I looked through this entire thread and I don't see that you prior posted which milligram scale from amazon you use. If you don't mind please post uri to your milligram scale for me and others. I see at least three and would prefer to buy one that is semi-durable and has worked well for others (e.g. you).

mdmvrockford wrote:IF I had a milligram scale THEN I would do what you do. But I am frugal (i.e. cheap) and have the <$20 recommended scale from Amazon that does not measure to milligram. Hence I use concentrate which I then add to 3.78L (1 gallon of water). I test the water with cheap TDS meter and values are in ballpark of 100mg per litre of potassium bicarbonate (and chemistry confirmed by "homeburrero" on prior water post).

I looked through this entire thread and I don't see that you prior posted which milligram scale from amazon you use. If you don't mind please post uri to your milligram scale for me and others. I see at least three and would prefer to buy one that is semi-durable and has worked well for others (e.g. you).

https://smile.amazon.com/gp/product/B07 ... UTF8&psc=1

Not that I have a dog in this fight. I just measure 2g K2CO3 into 5 gal. distilled water. Slightly higher than RPavlis, but only by a tiny bit.

mdmvrockford wrote:IF I had a milligram scale THEN I would do what you do. But I am frugal (i.e. cheap) and have the <$20 recommended scale from Amazon that does not measure to milligram. Hence I use concentrate which I then add to 3.78L (1 gallon of water). I test the water with cheap TDS meter and values are in ballpark of 100mg per litre of potassium bicarbonate (and chemistry confirmed by "homeburrero" on prior water post).

I looked through this entire thread and I don't see that you prior posted which milligram scale from amazon you use. If you don't mind please post uri to your milligram scale for me and others. I see at least three and would prefer to buy one that is semi-durable and has worked well for others (e.g. you).

You can get a mg scale for less than $20 on Amazon. The most inexpensive one that I see is $14:

https://www.amazon.com/UNIWEIGH-Milligr ... s9dHJ1ZQ==

Mine is fancy, luxurious, and full of ostentation. I spent $21:

https://www.amazon.com/Smart-Weigh-GEM2 ... 007&sr=8-6

I've had mine for about a year, and so far so good. I'm frugal too, and I'll never say what a dollar is worth to someone else. But $14-21? For the convenience, I'll make that purchase all day.

Thanks "sideshow." I saw at least three milligram scales on amazon. I wanted to know which one you and others had ownership experience with. Alas the milligram precision scale look to be like the 0.1 gram scales i.e. last at best 3 years and then need to buy new one.

mdmvrockford wrote:Alas the milligram precision scale look to be like the 0.1 gram scales i.e. last at best 3 years and then need to buy new one.

Maybe, but I use it a lot less than my .1 g scale. Basically only when I need to refill the reservoir. So maybe it'll last longer. Haven't had an issue yet.

Breville has just replaced our 920XL Dual Boiler for the second time in 5 years. What a great company to deal with! The machines may have suffered from scaling issues. A descale message never appeared on the 1st one; it's solenoid failed and the water dispenser developed a drip within 2 years. The replacement prompted for descaling after approximately 2 years then failed the same way a year later. The steam wand dripped on both but I understand from HB forum postings that's maybe not related to scaling.

I'd like to avoid scaling issues with this brand new 3rd machine but I'm reluctant to buy jugs of distilled water. I'm a little less reluctant to buy reverse osmosis treated water from a local water outlet in 18L bottles. However, we have an under-counter, 3-canister filtering system for our drinking water here in Vancouver, BC. A 1 micron, spun polypropylene sediment filter, a 5 mic carbon block cartridge and a 0.5 mic carbon briquette filter. The replacement filters are roughly $60 and get switched out every year or so. Would adding potassium bicarbonate to this water help to reduce scaling? Or will this only work with distilled or RO water?

My method is to make a 1:1000 concentrated solution that I store in a jar in the refrigerator.

20 grams of potassium bicarbonate into 200 ml. of water. It dissolves easily.

I then add 3.8 ml of concentrate into a gallon of water using a pipette. If you don't have lab pipettes I/m sure a 5 cc syringe would work to get ~ 4 ml concentrate. The concentrate lasts quite while.

pjackman wrote:I'd like to avoid scaling issues with this brand new 3rd machine but I'm reluctant to buy jugs of distilled water. I'm a little less reluctant to buy reverse osmosis treated water from a local water outlet in 18L bottles. However, we have an under-counter, 3-canister filtering system for our drinking water here in Vancouver, BC. A 1 micron, spun polypropylene sediment filter, a 5 mic carbon block cartridge and a 0.5 mic carbon briquette filter. The replacement filters are roughly $60 and get switched out every year or so. Would adding potassium bicarbonate to this water help to reduce scaling? Or will this only work with distilled or RO water?

Tap water in the Vancouver BC area is famously low in hardness and alkalinity, so unless you are on some special well source in that area you should not have scale issues with your setup. Adding a little potassium bicarbonate to Vancouver BC tap would do nothing to reduce scale risk, but might be OK if you're worried about corrosion and wanted to bring your alkalinity up to the oft-recommended minimum of 40 mg/L. But I don't think it's a worry here because that tap water is nicely free of ions like chloride that can cause corrosion.

The system you have now looks good to me for Vancouver BC water utility water with its 6 - 12 mg/L alkalinity and 2 - 13 mg/L total hardness (in CaCO3 equivalents). If you really want rpavlis-like water you could use the recipes here and just use your charcoal filtered Vancouver tap in place of distilled.