Hi all,

I have a RO system and am looking to install a BWT Bestmin Premium remineralization cartridge after it for use for espresso. There are three potential places where I could put it and was wondering which would be ideal (would love to avoid trial and error if possible):

- After membrane, before permeate pump
- After permeate pump, before RO water storage tank
- After RO storage tank, before espresso machine

Any suggestions?

Thanks!
David

david82 wrote:- After RO storage tank, before espresso machine

This is the standard location, and where BWT would tell you to put it. Besides remineralization, this filter is a carbon finishing filter that removes any particles or any off-tastes that might come from your accumulator tank.

david82 wrote:- After permeate pump, before RO water storage tank

There is an argument that by putting it here rather than putting it last in line you might smooth out the spike in mineral that you get when drawing the first cups of water from the system after it has been idle. (See this post: Plumbed into an RO tank. Help! ). If you did that your machine would then be getting water directly from the accumulator, so it might be a good idea to add a plain charcoal & particulates finishing filter in that line from the accumulator to the espresso machine.



If you want to get carried away with a custom arrangement of check valves and T fittings you could even consider rigging up a third option as used by the patented PrefectWater Full Contact system, (as discussed here: Reverse osmosis water system recommendation? ). This would make water go through the filter on its way into the accumulator and again on its way out to the espresso machine.


P.S.
For anyone wondering how the RO, permeate pump, accumulator, and finishing filter typically work together there's a nice online animated diagram by the Pure Water Products folks: https://www.purewaterproducts.com/artic ... pumps-work

homeburrero wrote:If you want to get carried away with a custom arrangement of check valves and T fittings you could even consider rigging up a third option as used by the patented PrefectWater Full Contact system, (as discussed here: Reverse osmosis water system recommendation? ). This would make water go through the filter on its way into the accumulator and again on its way out to the espresso machine

The engineer in me really likes this...

How does this perform relative to the mineral spine after long rests? Seems at first glance to be as bad or worse than the typical installed position after the accumulator, but since the accumulator water has already passed through the mineralization cartridge, the concentration gradient should be much lower, so perhaps it is better?

Thanks for sharing!

homeburrero wrote:This is the standard location, and where BWT would tell you to put it. Besides remineralization, this filter is a carbon finishing filter that removes any particles or any off-tastes that might come from your accumulator tank.


There is an argument that by putting it here rather than putting it last in line you might smooth out the spike in mineral that you get when drawing the first cups of water from the system after it has been idle. (See this post: Plumbed into an RO tank. Help! ). If you did that your machine would then be getting water directly from the accumulator, so it might be a good idea to add a plain charcoal & particulates finishing filter in that line from the accumulator to the espresso machine.



If you want to get carried away with a custom arrangement of check valves and T fittings you could even consider rigging up a third option as used by the patented PrefectWater Full Contact system, (as discussed here: Reverse osmosis water system recommendation? ). This would make water go through the filter on its way into the accumulator and again on its way out to the espresso machine.


P.S.
For anyone wondering how the RO, permeate pump, accumulator, and finishing filter typically work together there's a nice online animated diagram by the Pure Water Products folks: https://www.purewaterproducts.com/artic ... pumps-work

Thank you so much. This is why I love this place, somehow this site is essentially the last bastion of civility and knowledge on the Internet.

That third option you suggest at the end looks intriguing, even I understand what it's doing and it looks relatively straightforward to set up.

Thanks!

Jake_G wrote:How does this perform relative to the mineral spine after long rests? Seems at first glance to be as bad or worse than the typical installed position after the accumulator, but since the accumulator water has already passed through the mineralization cartridge, the concentration gradient should be much lower, so perhaps it is better?

That was my expectation, that it would be less spiky than the conventional arrangement, although I've not seen any data to support that. The water in the accumulator would be mineralized and at a near neutral pH so when it goes back through it should not pick up nearly as much mineral as the first time through. But thinking about the first cups after an overnight idle, the water would still be coming out of the filter with an overnight contact time, and may be about the same as having the filter in the conventional place.

The Perfect Water folks report pretty good average numbers (they say 30 - 60 mg/L on a typical RO setup) but don't tell us anything about the numbers after an overnight idle. Their standard remin filter reportedly uses simple food grade crushed marble which should be less spiky than a filter that contains a lot of Corosex or some other MgO source (e.g., calcined dolomite?*).


* Reiner Stanelle of BWT has reportedly said that the BWT Bestmin has some sort of pH correcting dolomite: Yet Another RO + Water Remineralization Setup Question