Express WaterModel 6 ROT600ALK Tankless RO with Remineralization
The tankless Model 6 with a sixth remineralisation stage, for thirty-eight dollars more.
$433
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Usability
Usability
This is the version of the Model 6 most people should buy, because thirty-eight dollars is a small premium to remove the single most common complaint about tankless RO, which is that the water tastes of nothing. Everything that makes the base Model 6 good carries over unchanged: 600 GPD, a 2:1 drain ratio, no pressure vessel and a filter alert on the unit. The compromises carry over too - 0.42 GPM at the faucet is half what a pressurised tank gives, it needs a mains outlet, and Express Water publishes total purified volume without a service interval. Nothing in the Model 6 range holds an NSF listing, and no mineral output range is published for the remineralisation stage, so the taste claim is the manufacturer's own. At $432.99 it is the most expensive drinking-water system Express Water sells and still carries a one-year warranty.
- 600 GPD with a 2:1 pure-to-drain ratio, the best water economy in the range
- Sixth stage addresses the flat taste that is the usual complaint about tankless RO
- No pressure vessel, frees the under-sink cabinet
- Filter-change alert built in
- Same footprint and weight as the five-stage version despite the added stage
- Faucet flow of 0.42 GPM is half what the tank systems deliver
- No NSF listing and no published mineral output range for the remineralisation stage
- Filter life given as total gallons with no time interval
- Requires a mains outlet under the sink
- Most expensive drinking-water system in the range, still on a one-year warranty
- Pump operation is audible
The ROT600ALK is the Model 6 tankless platform with a sixth stage that returns minerals to the permeate. Production is 600 GPD with a 2:1 pure-to-drain ratio and a 0.42 GPM faucet, and the unit carries a filter-change alert. Dimensions and weight are identical to the five-stage version at 15.8 x 18 x 6.1 in and 26 lbs.
Additional information
Specification: Express Water Model 6 ROT600ALK Tankless RO with Remineralization
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