If you want to get the best value for your money, we recommend the iSpring RCC7 5-stage reverse osmosis water filter.
It lacks some extras such as a remineralization filter and a permeate pump. But when it comes to filtering out impurities from your drinking water, it’s just as effective as other more expensive systems.
Read our full review of the iSpring RCC7 water filter below.
If you want an RO filter that produces mineral water, consider the iSpringRCC7AK, and if you want one with a UV filter, the 7-stage iSpring RCC7AK-UV is a right choice.
Get more top recommendations in our in-depth reverse osmosis water filter buying guide.
Filtration System Design
The iSpring RCC7 is a bit barebones compared to other more expensive RO water filters. It just comes with the essentials, nothing more.
If you are looking for an RO system with additional features such as a UV filter or a permeate pump, this is not it.
Though the design is basic, it’s good enough to provide clean and safe drinking water.
Just like other RO filters, the RCC7 removes hundreds of contaminants ranging from sediment to bacteria and viruses.
It does this using a 5-stage process, which we describe in more detail below.
The first three stages are for pre-filtration.
Pre-filtration removes impurities such as dust and chlorine that can clog the RO membrane or damage it.
By pre-filtering some of the impurities, the membrane is left to deal with the hardest-to-remove contaminants, which improves overall performance.
The first pre-filter is a sediment filter.
It removes large impurities suspended in water, including dust, rust, and silt. The filter is designed to hold large amounts of dirt and resist damage from a wide range of chemicals.
The filter housing is transparent so you can see how much dirt has been filtered from the water. This helps you determine when it’s time to replace the filters.
Next up is a GAC or granular activated carbon filter.
It removes chlorine and various other chemicals that affect the taste and smell of water. It also filters out any fine sediment that has passed through the sediment filter.
Water then goes through a carbon CTO filter. This one can remove smaller impurities that escaped the GAC filter.
It tackles tougher chemicals like chloramines, certain pesticides, hormones, pharmaceuticals, and other organic chemicals.
By now, most of the impurities remaining in the water are dissolved salts and other inorganic compounds like chromium and arsenic.
Most of the biologicals – bacteria, viruses, and cysts –also remain untouched, for now.
The semi-permeable membrane that is at the heart of the RCC7 filters out all remaining contaminants virtually.
The membrane has holes as small as 0.0001 microns. That means anything larger than this gets filtered out.
That includes heavy metals, dissolved salts, and microorganisms.
The water that comes out of the other side of the membrane is considered pure. It has extremely low levels of impurities.
There’s one more filter to make sure your drinking water tastes and smells fresh.
When the purified water goes into the tank, it can take up some mild but unpleasant smells and tastes, especially if it sits in the tank for too long.
The post-filter removes these tastes and odors. It is located in-line just before the faucet.
This way, every time you open the faucet, you get fresh, great-tasting purified water.
There is no difference in the performance of filtration between the RCC7 and a more expensive 6 or 7-stage system.
The water may taste a little flatter because it lacks minerals, but it is just as pure as that from any other RO filter.
The 5-stage filtration process removes hundreds of impurities, including heavy metals, hardness minerals, fluoride, chromium, microorganisms, and chemicals.
It works just as well for treated city water as it does well water.
But you should replace the filters sooner if you are using well water since the filters are removing higher amounts of impurities such as scale and iron.
The RCC7 produces 75 gallons of purified water every day. That’s more than enough for most families.
The only thing that might disappoint you a bit is the flow rate out of the faucet.
Because the filter doesn’t have an integrated pump, the water comes out fairly slowly. You can work around this by filling large water bottles beforehand for easier access to drinking water.
Another downside of not having a built-in pump is that it wastes more water than systems with a permeate or booster pump.
Because of backpressure from the pressurized reserve tank, a fair amount of water goes down the drain — specifically, 3 gallons for every 1 gallon of pure water.
If you are concerned about high water bills, buy a booster or permeate pump and connect it to the RO system.
It will increase the pressure of water and reduce how much water is wasted.
It will also increase the water’s flow rate.
Installation and Maintenance
The iSPring RCC7 is designed for DIY installation. With basic tools–just a power drill really –you can set up the filter under your sink in an hour or two.
The manual has clear instructions with plenty of images to guide you.
Everything you need comes with the installation kit including ½” and 3/8” feed water adapters, all the necessary valves and connectors, food-grade tubing and a metal faucet with a brushed nickel finish.
The tubing is color-coded to make it easier to figure out where to connect it.
There’s a specific tube for the drain water, and another for the feed water, one that goes to the tank and another that connects to the faucet.
To connect the tubes, you push them into the connectors. You don’t need any tools.
The entire RCC7 system – filter setup plus the tank – take up quite a bit of space under the sink. But it’s not as big as other RO filters.
It should fit easily under most sinks and leave some space for other things.
If your under-sinks pace is too cramped, you can set up the filter in your basement and run a tube to the sink.
Depending on your water pressure, you may need a booster pump to push the water over the longer distance.
On average, you’ll need to replace the filters once a year. If your water quality is low (e.g., if you are using well water), you might need to do it twice a year.
The pre-filters and the post-filter have a lifespan of 6-12 months. The RO membrane is good for 2-3 years.
To ensure you replace the filters at the right time, we recommend buying a TDS meter. Take a measurement immediately after installing the system then once a month after.
When TDS levels start to rise, it’s a sign that the filters are clogged and allowing some impurities through.
Other than regularly checking for leaks, no other maintenance is required.
What We Like the Most About the iSpring RCC7 5-stage RO System
What We Don’t Like
The Home Master TMAFC-ERP Is Perfect For You If...
You are looking for an affordable reverse osmosis system that is highly effective at filtering water, is reliable and is easy (and cheap) to maintain.
Our Bottom Line
The iSpring RCC7 is one of the best priced RO systems. It’s affordable while providing the same level of performance as other pricier systems.
If you don’t mind non-mineralized water, by the slightly higher water wastage and a lower flow rate (all problems you can solve, by the way), the iSpring RCC7 is a great buy.