I hate you

I called the local supplier and asked to return the 1 head and get a 3 head instead. I'll use 3 filters under the sink going like this: MC2 > ESO7 > MH2 > tank > pump > accumulator > Claris > pressure regulator > 2 way for machine and filter.

Final set up

Ad-85 wrote:I hate you

Hope that's in jest. I did say that I thought your plan would work. I'm not sure why you are changing to this new approach. Is your local supplier advising you to do all that?

PS, here's is what I thought you had suggested and that I thought would work:

undersink waterline ---> QC71 w BH2 (or MH2) ---> tank
--> (transport the filled tank over to espresso cart) --->
tank ---> pump ---> accumulator --> Claris Everpure ---> espresso machine.

You would tee off that line to the espresso machine so that you could flush newly installed filters, and take samples.

The water in the tank is charcoal filtered and scale inhibited, not softened. The water going to the machine is particle and charcoal filtered again, which will take care of odors from the accumulator, and softened/decarbonized as needed to prevent limescale by the Claris ion-exchange with the adjustable bypass.

I truly hope this helps more than it annoys, and let me know if I've misunderstood what you are trying to do here.

homeburrero wrote:Hope that's in jest.

Lol it is

Local supplier wants to sell more than giving advice (probably knows nothing too).

Well, I read your reply and freaked out

I think it's an overkill but will see. I could always buy the 1 head and go back to my initial plan. When I saw you recommending the eso7 I read it needs a pre filter so I had 2 choices (MC2 which the local supplier carries and the 7bc5 which I liked but not available locally).

@homeburrero Thanks man and I was kidding! 3 filters under sink might be a bad idea but nothing wrong with giving it a try.

I have just attached a BWT BestMin cartridge to my RO system. With the use of an API dropper test, I measured my water to have the following characteristics:

Pure RO (no Bestmin):
GH: 1°D (17.8 ppm)
KH:1°D (17.8 ppm)
pH (pool test kit): 6.6

RO with BESTMIN
GH: 2°D (35.6 ppm)
KH:2°D (35.6 ppm)
pH: 8.2

I am concerned about my alkalinity being below 40ppm. Can I expect corrosion with these characteristics? Am I correct that scaling should not be an issue given the lack of chloride in RO water and low GH of my water?

Bestflex head bypass set to 0 (apparently bypass settings have no effect when used with bestmin)

Any help would be greatly appreciated. Thanks

I have just attached a BWT BestMin cartridge to my RO system.
...
I am concerned about my alkalinity being below 40ppm. Can I expect corrosion with these characteristics? Am I correct that scaling should not be an issue given the lack of chloride in RO water and low GH of my water?

That's about par for the mineralization you get from a good remin cartridge. They don't add much and generally don't add enough to cause any scaling issues. Your GH and KH numbers are low enough that you don't expect scale issues, and your alkalinity (KH) is good enough that you needn't worry about corrosion despite the lowish GH. You do expect low chloride ion out of an RO with no bypass blending, and that helps to keep corrosion risk low.

If you test it with a 10 ml sample rather than 5ml that comes with the API kit, you will get better precision, so that each drop corresponds to 8.9 ppm CaCO3.

Thanks Pat! This is both helpful and reassuring.

I have retested my alkalinity (KH) using 10, 15, and 20ml samples.

10ml and 20ml tests:
1.5 °D ( 26.7ppm)
Colour change was very subtle. Very faint pale yellow-orange.

15ml test
1.665 °D (29.6ppm)
More prominent yellow-orange colour change.

I think it is safe to assume that my KH falls somewhere between 26 and 30ppm. GH was 35.6 for 10ml test.

Is my alkalinity still adequate?

homeburrero wrote:That's about par for the mineralization you get from a good remin cartridge. They don't add much and generally don't add enough to cause any scaling issues. Your GH and KH numbers are low enough that you don't expect scale issues, and your alkalinity (KH) is good enough that you needn't worry about corrosion despite the lowish GH. You do expect low chloride ion out of an RO with no bypass blending, and that helps to keep corrosion risk low.

If you test it with a 10 ml sample rather than 5ml that comes with the API kit, you will get better precision, so that each drop corresponds to 8.9 ppm CaCO3.

Liverbird_8 wrote:Is my alkalinity still adequate?

Yes, still adequate. The conventional guidance, including from the current SCA is to shoot for 40 mg/L (as CaCO3) or higher alkalinity for corrosion risk reasons. That guidance allows for the fact that water may contain some corrosive ions, especially chloride. If you are using RO without a blend-back valve you expect those ions to be very low and you can get away with less alkalinity. The expected pH of your remineralized water, even after exposure to atmospheric CO2 and associated carbonic acid will be nicely above neutral -- close to 8.

P.S.
I wouldn't worry over the fact that your water is low in mineral content. Many cafes use natural water that is that low or even lower in mineral content and are known to make well respected coffee and espresso. Here is a listing showing the KH:GH numbers (in CaCO3 equivalents) for a few soft water areas:

KH:GH * ppm as CaCO3
Oslo: 30:40 (Oslo water)
Melbourne: 15:27 (https://www.aquasafe.com.au/wp-content/ ... alysis.pdf)
Vancouver BC: 10:11 (Plumbing in with very soft water supply)

N Seattle: 19:23 (Seattle water)
Portland OR (Bull Run): 10:7 (How Is My Water - Any Treatment Needed?)
Atlanta (Marietta): 23:32 (Water for my new espresso machine)


* Edit addition Note: I think it's possibly more conventional to specify it as GH:KH rather than KH:GH as I did in this post.

Thanks again Pat, you're a life saver!

homeburrero wrote:Yes, still adequate. The conventional guidance, including from the current SCA is to shoot for 40 mg/L (as CaCO3) or higher alkalinity for corrosion risk reasons. That guidance allows for the fact that water may contain some corrosive ions, especially chloride. If you are using RO without a blend-back valve you expect those ions to be very low and you can get away with less alkalinity. The expected pH of your remineralized water, even after exposure to atmospheric CO2 and associated carbonic acid will be nicely above neutral -- close to 8.

P.S.
I wouldn't worry over the fact that your water is low in mineral content. Many cafes use natural water that is that low or even lower in mineral content and are known to make well respected coffee and espresso. Here is a listing showing the KH:GH numbers (in CaCO3 equivalents) for a few soft water areas:

KH:GH ppm as CaCO3
Oslo: 30:40 (Oslo water)
Melbourne: 15:27 (https://www.aquasafe.com.au/wp-content/ ... alysis.pdf)
Vancouver BC: 10:11 (Plumbing in with very soft water supply)

N Seattle: 19:23 (Seattle water)
Portland OR (Bull Run): 10:7 (How Is My Water - Any Treatment Needed?)
Atlanta (Marietta): 23:32 (Water for my new espresso machine)

Sorry for being pedantic but has anyone else experienced bubbles forming on the walls of the container in which water is stored. This only happened after installing a BESTMIN cartridge to my RO system. Bubbles begin to accumulate on the walls within an hour. I am aware that new filters will have small bubbles forming cloudy water that dissappear after the system is flushed/bled. This looks a bit different though. Are these harmless or could they potentially damage an espresso machine?