BWT Bestbarista ROC COFFEE Reverse Osmosis System

For over a decade we’ve partnered with BWT to provide our customers with great tasting water to brew their espresso and protect the longevity of their machines. We offer several filtration cartridges to address varying degrees of water hardness, and now, we’re pleased to introduce a complete reverse osmosis and remineralization system, the BWT Bestbarista ROC Coffee.

 

The Bestbarista ROC Coffee is a two cartridge RO system from BWT and the first we’re offering here at Whole Latte Love. The reasoning is simple: this system can reliably resolve water hardness and chloride issues in drinking water anywhere, meaning that the resulting water will be safe for anyone to use in their machine. Water is softened by passing through the RO membrane in the first cartridge, it’s then remineralized with a blend of magnesium and silicate to improve the flavor of your coffee and protect your machine from corrosion.

How it Works

Without getting too technical, the Bestbarista works by using an internal loop to guarantee that water is properly softened. The membrane cartridge removes 97% of content from the water and the efficiency of the system 50%. What that means is that if you filtered two gallons of water, you’d get 1 gallon of clean, filtered water (also referred to as permeate) and 1 gallon of water that contains all of the removed substances (concentrate). The permeate is passed on through the remineralization cartridge and concentrate is removed through a waste water drainline. However, that’s not telling the whole story.

BWT’s Demixo

In order to earn an NSF certification, BWT created a system that prevents spikes in TDS (total dissolved solids) that can occur when water sits in the system for an extended period of time (due to inactivity). The system, known as “Demixo,” uses a conductivity probe to actively monitor the TDS of the filtered permeate water. This is where the companion app comes into play.

BWT’s app for the Bestbarista ROC COFFEE allows you to (among many things) set your target TDS for your permeate (filtered water). The conductivity probe checks the target that you set in the app and will continue to recirculate the permeate back through the RO membrane until it reaches your target. At that point, the system will allow the permeate to pass through the remineralization cartridge. However, just because you have a target that serves as the minimum threshold, the permeate may actually reach an even lower TDS than your target.

As a rule of thumb, your rinsing target should be 10% of the TDS of your raw water that you are feeding into the RO system.

For example, if your raw water has a TDS of 100, your rinsing target should be a TDS of 10.

It’s very important to set your TDS target appropriately in the app. The rinsing cycle runs and will reach 100% once it’s finished. If the TDS of the permeate has not reached your target by the rinsing cycle completes, the system will assume that your membrane cartridge is no longer properly filtering your water and needs to be replaced.

Pre-Filtration

One thing that you can do to reduce the time it takes to reach the rinsing target and to extend the life of your RO membrane is to pre-filter water that’s being fed into the system. To do this, BWT recommends installing a BWT Besttaste cartridge between your raw water and your RO system. The Besttaste has a 200 µm sediment filter that helps to reduce the load on your membrane cartridge.

The Cartridges

Unlike many systems out there that can use anywhere from 3 to 5 cartridges, the Bestbarista ROC COFFEE uses just two, making it much easier to keep track of replacement.

Bestaqua 14

The Bestaqua 14 is a high-performance reverse osmosis membrane cartridge that is 97% effective in removing unwanted substances from the raw water. These can include but are not limited to:

Limescale (Calcium Carbonate), Gypsum (Calcium Sulfate), Particles, Calcium, Sodium, Potassium, Sulphate, Carbonate, Chloride, Off-Flavors, Chlorine

The Bestaqua cartridge has a lifespan of 12 - 24 months, but should be replaced no later than 24 months. The membrane has a capacity to filter 120 L of water per hour.

Bestbarista 14

The second cartridge, the Bestbarista 14 is a remineralization cartridge that optimizes the filtered water for use in espresso machines. BWT uses a mix of Calcium Bicarbonate, Magnesium Oxide and Silicates to help the water absorb more magnesium.

As a result, water that has been remineralized through the Bestbarista 14 cartridge actually has a higher PPM of 80-120ppm compared to water that passes through the Bestmin cartridge which is around 30-50ppm. It's also worth noting that because the water is remineralized, it does not need to be stored in a special tank and can be sent directly from the Bestbarista ROC COFFEE directly to your machine.

The total capacity of the cartridge is 2,000L or 530 gallons and the cartridge has a lifespan of 6 - 12 months but should be replaced no later than 12 months.

Changing the Cartridge

Just like the water filtration systems that BWT produces, changing the cartridges on the Bestbarista ROC COFFEE is incredibly simple. Just remove the existing cartridges. You have to take both out for the rinsing process. Install the replacement cartridge as well as the included blind cap in order to rinse without flushing any of the rinsed water into the other cartridge.

The Step Up & Down Transformer

Included with each Bestbarista ROC COFFEE is a 220V Step Up & Down Converter that can be used to convert from 110V to 220V and vice-versa. The transformer is packed in a separate box to the rest of the RO system, so it’s important to open and account for everything you receive in your order before discarding or storing any boxes that were part of your order.

When To Use RO

Reverse osmosis is use for more than just softening water by removing minerals. It's also used to correct for dissolved salts such as chlorides that increase the likelihood of corrosion in the metals inside of espresso machines. Water conductivity is measured by units known as micro-Siemens. To determine whether or not reverse osmosis and remineralization are necessary, BWT suggests the following:

If the conductivity in micro-Siemens, multiplied by 0.6 is higher than the water's total hardness in ppm, then reverse osmosis and remineralization are necessary.

So for example, if your water had a conductivity of 200 and a Total hardness of 100 ppm, 200 * 0.6 = 120 which is greater than 100 ppm, meaning that you would need to remove the dissolved salts via reverse osmosis to prevent corrosion.

If you're a café owner with multiple locations in areas of varying degrees of water quality, you may still want to use the Bestbarista ROC COFFEE in order to ensure that all of your shops are brewing with the same water, even if RO isn't strictly necessary to produce water that's safe for your equipment.

How to Test

For water hardness, we recommend using BWT's water hardness test kit to measure the total hardness and alkalinity. These numbers are used to help determine which water filtration solution is best suited for your water. For conductivity, a water conductivity tester (these are available online and in hardware stores) can be used, or if available, that information can also be obtained from your municipal water supplier.

To determine the TDS of your water in ppm for the purposes of comparing against its conductivity, simply multiply the result of your test for total hardness or °d GH by 17.9. So for example, if your total hardness in °d GH is 8, it would be 143.2 ppm. Then you can compare that to your conductivity to determine if RO is necessary.

Other Filtration Solutions

In addition to reverse osmosis, BWT offers a wide range of traditional water filtration solutions, both for use in a water line, in a water tank, or in pitchers that produce filtered and remineralized water for your machine. For the rundown on those options, check out our guide below.

Final Thoughts

We've been wanting to offer a reverse osmosis system for a number of reasons, not the least of which is to help protect espresso machines from mineral buildup and corrosion. This latest solution from BWT not only makes any drinkable water safe for use in any espresso machine, but remineralizes and optimizes it to improve the taste of the coffee you're brewing.

Whether you're a café or home enthusiast, the simplicity and efficiency of the Bestbarista ROC COFFEE should certainly warrant consideration to help you brew your best and protect your investment.

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