GREATWELL ROG400 Tankless Reverse Osmosis Water Filtration System with 400 GPD RO Filter 1.5:1 Pure to Drain Ratio and Drinking Water Faucet
$598.99
About this item
- ROG400 is a tankless reverse osmosis system. The vertical filter placement design saves more than 30% of space under the sink compares to a horizontal design. A leak-free integrated water route and filter change indicator.
- The PAC filter is a combination of two sediment filters and a carbon filter that removes sand, rust, chlorine, odor, and smell. The RO membrane removes up to 99% of over 1,000 contaminants, including PFAS, lead, fluoride, arsenic, asbestos, and more for up to 3 years. The AC or the active carbon filter made from coconut shell further polishes water removing odor and bad taste.
- With a built-in water pump and GE reverse osmosis membrane rated at 400 GPD, the water flow rate from ROG400 is at 0. 3-0. 4 gal./min., with a pure to wastewater ratio (up to 1.5 : 1).
- DIY installation and future filter replacement. The unit can be connected to the ice maker/refrigerator. It includes an artisan-style stainless steel drinking water faucet.
- At GreatWell, we only use quality components tested by an independent 3rd party against NSF/ANSI standards. Lifetime technical support provided by our dedicated support team based in Atlanta, GA.
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GREATWELL Tankless Reverse Osmosis Water Filtration System with 400 GPD RO Filter 1.5:1 Pure to Drain Ratio and Drinking Water Faucet
$598.99
- Availability: In Stock
- Model: ROG400
- Manufacturer: iSpring
Write Review
Tom Malkowski | 
2019-06-17
I had to email customer service about the fact that my tds was over 300. I believe it was 477ppm which is barely below the limits allowed by the epa. I didnt know this until I received the unit and a tds tester on the same order. They recommend getting a water softener if its over 300ppm. The man who responded to me was thorough and knowledgeable. He just told me I would need to replace the membrane more frequently maybe after 1.5yr. I will at some point in time get a water softener to protect my appliances but its not something I can afford at this moment. Installation was pretty easy I mostly just followed the picture that tells where each piece of tubing goes. Water tastes good not quiet like bottled RO but thats because they add minerals for taste to bottled RO. I will get used to it eventually. I calculated it based on cost per gallon of water from my supplier and cost of 1gal of distilled water which is cheaper than the RO bottled water I get.

2019-06-17
I had to email customer service about the fact that my tds was over 300. I believe it was 477ppm which is barely below the limits allowed by the epa. I didnt know this until I received the unit and a tds tester on the same order. They recommend getting a water softener if its over 300ppm. The man who responded to me was thorough and knowledgeable. He just told me I would need to replace the membrane more frequently maybe after 1.5yr. I will at some point in time get a water softener to protect my appliances but its not something I can afford at this moment. Installation was pretty easy I mostly just followed the picture that tells where each piece of tubing goes. Water tastes good not quiet like bottled RO but thats because they add minerals for taste to bottled RO. I will get used to it eventually. I calculated it based on cost per gallon of water from my supplier and cost of 1gal of distilled water which is cheaper than the RO bottled water I get.
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ROG400 Manual