iSpring 6-Stage Superb Taste Under Sink RO Water Filter System Review

The iSpring RCC7 has different variations and among them, RCC7AK is highly rated and most popular.

You will get a filter as RCC7 along with remineralization filter by spending a few more dollars. The water has a bland taste when it is purified by reverse osmosis because all the dissolved minerals which add some flavor to the water have been removed by reverse osmosis and becomes slightly acidic.

But  RCC7AK adds safe minerals to the water and makes it more alkaline due to this water becomes fresher which many people prefer.

Water Filtering Capacity Of iSpring 6-Stage RCC7AK

Its capacity for producing water is higher among other water filters. Water is produced by going through 6 stages of filtration and per day it can produce up to 75 gallons of purified water.

Though its purified water producing capacity is higher, it wastes up to 3 gallons of water to produce one gallon of filtered water. This data is just an average as compared to other systems but this will vary according to your feed water pressure.

It comes along with pressurized storage tank and faucet and anyone with basic DIY skills can install in 1 hour.

Design Of Filtration System

The RCC7AK has a plastic filter holder in which cartridge type filters are implanted. Filters which are used in Home Master systems are easy to change but others are not the same as Home Master systems but in the case of the iSpring system, filters are relatively simple and easy to change.

You need to lose the housing along with the plastic spanner wrench supplied with the system for changing filters and now unscrew with the help of hand ( there may be a chance that some water may be spilled out at this stage) and remove the old filter. Now push the new filter in and apply some lubricant at the “O” ring and then screw. And finally, with the help of spanner, tighten it up.

Water Efficiency

For an RO system, water efficiency is a measure of how much amount of water is needed to produce 1 gallon of purified water. There are some systems which require 5 gallons of water to produce 1 gallon of purified water and rest 4 gallons of water are wasted. But in the case of RCC7AK, only 3 gallons of water is wasted in producing 1 gallon of purified water. It is the general average water waste across all the systems but this can vary according to the pressure and temperature of the feed water.

Easy Installation of iSpring 6-stage

Before you start- there should be a pressure between 45 to 70 psi as this system working is based on feed water pressure. There is a need to use a regulator if the pressure is more than 80 psi and a permeate pump is required if pressure is below 40 psi.

Anyone with basic DIY skills can install RCC7AK within an hour. A plumber can install this if you are not feeling confident in installing it.

You need to drill a hole in the sink top which is used for pure water faucet and you can say that for the whole installation, it is the potentially difficult part and if there is already a hole for a soap dispenser or anything else, there is no need to make another one.

There is some improvement in installation and owner’s manual but before going to this, you need to take a look at the installation video from iSpring. With step-by-step processes,  you can go through all the stages. There is also the demonstration for changing the filter cartridges and also a few handy tips in the video.

This need to keep in mind that iSpring provides locking connectors and if you know about push fit connectors then this also need to keep in mind. You need to remove the clip which is used by these devices before you going to push the plastic pipe in place.

Click here to watch this filter installation video.

System Specifications and it’s Working

There are total 6 stages of filtration in this and if the water is not going to all the technical “ins and outs” then the resulting water which is coming out of your faucet which is free from organic and inorganic contaminants will do not do any good to your health. So it becomes necessary that water should go through all the six stages.

Unlike 5 stage RO-filters, the 6th stage makes the natural pH balance of your water after filtering. This filter not only provides clean, odor free and fresh water but also adds a soft silky feel which is very perfect for sensitive skin.

This system uses reverse osmosis filtration like the 5-stage model which means a membrane is present there for helping in the filtration process. By using this type of system helps in letting good minerals in the purified water.


Superior Water Filtration Process

→ Top Notch Alkaline Filter

RO membrane removes helpful minerals along with harmful pollutants and due to this, a standard 5 stage RO system produces water slightly acidic and whose pH value is 7.0 or less.

While the 6th stage is an Alkaline Remineralization filter and RCC7AK helps to balance the alkalinity by restoring the healthy minerals due to which taste of water increases. It does not reduce the quality for quantity and uses the all natural mineral stones.

→ Water Quality

This product is tested annually by WQA and certified that it can remove up to 99.99% harmful contaminants that appear commonly in the water supplied by the municipality. Its all parts like tubes, filters, tanks, and water-contacting parts are manufactured with FDA (CFR-Parts 174) and NSF/ANSI standard which results in certification of WQA Gold Seal.

Due to its multi-layered filter system, it is capable of providing protection against more than 1,000s of different contaminants like fluoride, lead, mercury and more. Each stage of the filter system improves the water quality progressively.

→ What does it include?

Apart from providing the great taste of water by maintaining natural pH balance, you will also get all the things which needed to install this water filter. It also includes a storage tank whose capacity is to store 3.2 gallons of water and due to this, there is no need to wait for the water that goes through the filtration process before reaching to your glass. Undoubtedly, it also includes a faucet which is fitted on your sink along with all other attachments.

Points To Consider

  • It is better to take help from a professional to install the system if you are not a DIY person. It doesn’t mean that it is difficult to install the system but if you want to set the system up to your fridge, then you may face some complications.
  • For heavy usage, you need to change the filters after every six months and for light usage, you can change once in a year as recommended by the manufacturer. But for testing water to make yourself comfortable, you can also get a water testing kit to test the filtered water on a regular basis.
  • If you are looking for a filtration system which can provide you the water taste like water from a bottle and also by spending affordable money then this is definitely the best option you can go.


  • It improves the taste and raises the pH level
  • 3.2 gallon of water storage tank
  • 1-year money-back guarantee and a 3-year manufacturer warranty
  • It can produce up to 75 gallons of pure water per day
  • It can remove up to 98% of chemicals and other contaminants
  • There is a water leakage alarm in the kit
  • There is lifetime customer support
  • Replacement filters are inexpensive


  • There is wastage of 3 gallons of water on every 1 gallon of purified water
  • Life of filter is shorter than some other competitor

Conclusion – iSpring Under Sink Drinking Water Filter System

The iSpring RCC7AK is very easy to install and anyone can install it in 1 or 2 hours and this is highly appreciated in its online review on Amazon and also it is very economical.

In a very economical way, you can get very popular RCC7 remineralization filter.

One thing is to concern that the lifetime of the filter is short as compared to other competitors in the market. But also this shorter life can be balanced by its lower cost of iSpring cartridges.

By considering its price, features, quality, the RCC7AK is highly recommended for the RO system.

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