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
Triple the Savings, Triple the Joy!
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
Franky | 
2019-07-10
This product is simple to install, the water quality is very good, after a week of use, I no longer use the water to add chlorine, save my trouble, also save my money, my fish and coral are very well alive
2019-07-10
This product is simple to install, the water quality is very good, after a week of use, I no longer use the water to add chlorine, save my trouble, also save my money, my fish and coral are very well alive
techteachok | 
2019-09-01
Bought this to replace 15 year old "tank" based RO water filter. My tank died (bladder went) and without a tank to buffer and deliver a few gallons quickly - my old 25 gal per day rating on the RO was delivering its little heart out at its rated output of a little over a gallon an hour. Basically, put a gallon container under it, turn on, and come back in an hour. I wanted to get a better faster fill and not have a 5 gallon tank under the sink.
After install it took 2.5 min to fill a gallon container - much better than the "mathematical" calculation from 400 gal/day (3.6 minutes per gallon). Lastly, I like the ability to change the filters in the front of the unit, the wheels for easy movement under the sink, and how easy it was to install as a replacement.
Completely understood to get the performance of over 400 gal/day with a tankless system, the old style tank was replaced by a pump built into the water filter - BUT, didn't expect the pump to be as noisy as it is. Enough to stop conversation in the kitchen around the sink with folks saying what the heck is that noise. It would have been nicer to have a more silent running pump, which is my only real complaint. Took off 1 star for noisy pump.
Edit 5/1/2021: Read all the complaints about no filters available - I see they are available on Amazon, and I purchased a set from my local Home Depot, so, I don't understand the comments about no filters available unless you are in the middle of a desert.
2019-09-01
Bought this to replace 15 year old "tank" based RO water filter. My tank died (bladder went) and without a tank to buffer and deliver a few gallons quickly - my old 25 gal per day rating on the RO was delivering its little heart out at its rated output of a little over a gallon an hour. Basically, put a gallon container under it, turn on, and come back in an hour. I wanted to get a better faster fill and not have a 5 gallon tank under the sink.
After install it took 2.5 min to fill a gallon container - much better than the "mathematical" calculation from 400 gal/day (3.6 minutes per gallon). Lastly, I like the ability to change the filters in the front of the unit, the wheels for easy movement under the sink, and how easy it was to install as a replacement.
Completely understood to get the performance of over 400 gal/day with a tankless system, the old style tank was replaced by a pump built into the water filter - BUT, didn't expect the pump to be as noisy as it is. Enough to stop conversation in the kitchen around the sink with folks saying what the heck is that noise. It would have been nicer to have a more silent running pump, which is my only real complaint. Took off 1 star for noisy pump.
Edit 5/1/2021: Read all the complaints about no filters available - I see they are available on Amazon, and I purchased a set from my local Home Depot, so, I don't understand the comments about no filters available unless you are in the middle of a desert.
paris moshir |
2019-04-11
I had it installed in my kitchen under sink. Easy to install. The pressure was low. I contacted the company and they replaced it with a new one and it works perfectly now. The Greatwell representatives were very cooperative and helpful. Thank you Greatwell staff.
2019-04-11
I had it installed in my kitchen under sink. Easy to install. The pressure was low. I contacted the company and they replaced it with a new one and it works perfectly now. The Greatwell representatives were very cooperative and helpful. Thank you Greatwell staff.
Angel |
2018-10-31
purchased this unit about 3 weeks ago. So far, I am very happy with the product. You can certainly taste the difference in the quality of the water, particularly if you use the purification feature.
If anything changes in the next few months, I will reassess my rating and will update my comments. For now, it is a solid 5 stars. The feature I like the most is the design, which helps prevent water leaks. This was one of the key concerns I had when I was doing research to purchase this product, as many of the products in the market are susceptible to water leaks.
2018-10-31
purchased this unit about 3 weeks ago. So far, I am very happy with the product. You can certainly taste the difference in the quality of the water, particularly if you use the purification feature.
If anything changes in the next few months, I will reassess my rating and will update my comments. For now, it is a solid 5 stars. The feature I like the most is the design, which helps prevent water leaks. This was one of the key concerns I had when I was doing research to purchase this product, as many of the products in the market are susceptible to water leaks.
Cyrus |
2020-05-01
Installed it about 3 weeks ago and it's been working great. Pretty simple to install, just a few hoses and the plug. Hardest part was drilling into my quartz countertop for the faucet. Which looks great too. I plan on hooking it up to my ice maker. Instructions were minimal but it is a pretty straight forward install. The water tastes great.
2020-05-01
Installed it about 3 weeks ago and it's been working great. Pretty simple to install, just a few hoses and the plug. Hardest part was drilling into my quartz countertop for the faucet. Which looks great too. I plan on hooking it up to my ice maker. Instructions were minimal but it is a pretty straight forward install. The water tastes great.
MARLA |
2020-12-07
This is AWESOME! If you are on a well and have nitrates or bacteria this is the ticket! No tank or bladder to worry about and fits under the sink. Do not need a high PSA either. Update, filters are available from Home Depot.
2020-12-07
This is AWESOME! If you are on a well and have nitrates or bacteria this is the ticket! No tank or bladder to worry about and fits under the sink. Do not need a high PSA either. Update, filters are available from Home Depot.
David H |
2019-04-23
Installed at home under sink and it is working very well. I like how compact it is, the ease of filter change, and that it requires no Bladder tank. Delivers more water and faster than my previous unit. Very happy with the unit so far and I've had it for several months now. Update 10-13-2020. Had to change out the faucet and Richard at iSpring in the support department was very helpful and even replaced the faucet no charge even though technically out of warranty. Thanks Richard at iSpring! much appreciated.
2019-04-23
Installed at home under sink and it is working very well. I like how compact it is, the ease of filter change, and that it requires no Bladder tank. Delivers more water and faster than my previous unit. Very happy with the unit so far and I've had it for several months now. Update 10-13-2020. Had to change out the faucet and Richard at iSpring in the support department was very helpful and even replaced the faucet no charge even though technically out of warranty. Thanks Richard at iSpring! much appreciated.
Concetta M Ragonese |
2021-03-26
I HAVE HAD THIS ROG400 FOR 1 YEAR. I PREVIOUSLY HAD A WATER FILTER THAT USED LOTS OF WATER.
I COULD NOT BELIEVE HOW MUCH THIS UNIT CUT MY WATER BILL. IT WAS TIME FOR ME TO PUT A NEW FILTERS AFTER ONE YEAR. I CALLED THE ISPRING MANUFACTURE FOR ASSISTANCE IN STALLING THE FILTERS. I SPOKE TO DON AND HE WAS VERY, VERY. HELPFUL. THIS IS THE BEST WATER FILTER I HAVE EVERY HAD.
2021-03-26
I HAVE HAD THIS ROG400 FOR 1 YEAR. I PREVIOUSLY HAD A WATER FILTER THAT USED LOTS OF WATER.
I COULD NOT BELIEVE HOW MUCH THIS UNIT CUT MY WATER BILL. IT WAS TIME FOR ME TO PUT A NEW FILTERS AFTER ONE YEAR. I CALLED THE ISPRING MANUFACTURE FOR ASSISTANCE IN STALLING THE FILTERS. I SPOKE TO DON AND HE WAS VERY, VERY. HELPFUL. THIS IS THE BEST WATER FILTER I HAVE EVERY HAD.
Zmanrick |
2021-05-11
I have not had this unit very long, however the filter light has not triggered a need for the pre-filters yet. The last filter system that starts with a "B" needed filters every two months!
2021-05-11
I have not had this unit very long, however the filter light has not triggered a need for the pre-filters yet. The last filter system that starts with a "B" needed filters every two months!
T. Halchuk |
2020-06-17
I used this unit on a cottage that has well water. I have issue with fine sediment and tannins in the water.
The install was relatively easy based on my undersink plumbing. The water flow is slow but acceptable (low input pressure). There is a slight humming when unit is running. My nephews mentioned the water tastes good.
I contacted the seller's support person, Francis about my specific water issues. He walked me through all my concerns
I would buy this again.
2020-06-17
I used this unit on a cottage that has well water. I have issue with fine sediment and tannins in the water.
The install was relatively easy based on my undersink plumbing. The water flow is slow but acceptable (low input pressure). There is a slight humming when unit is running. My nephews mentioned the water tastes good.
I contacted the seller's support person, Francis about my specific water issues. He walked me through all my concerns
I would buy this again.
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