iSpring RCC7AK 6-Stage Reverse Osmosis System

The iSpring RCC7AK is an upgraded version of the RCC7 model with the addition of a nice extra filter. It can filter out all types of contaminants and enrich the water in the same process giving you a healthier, natural-tasting, clean drinking water.

This is our pick for the best under sink reverse osmosis system.

Read Now:

Excellent Filtration Process

The iSpring RCC7AK Reverse osmosis system features a multi-layered filtration process designed around 6 very efficient filtration stages specially tailored to progressively remove all types of contaminants and improve the water quality.

The first three stages are pre-filters consisting of polypropylene sediment filter in the 1st stage, GAC filter in the 2nd stage and a carbon block filter in the 3rd stage.

These three filters trap all the sediments and particles that are larger than 5 microns and more importantly removes chlorine, chloramines and other chemicals present in the water.

The fourth stage where the magic happens sits a quality RO membrane which eliminates all the remaining contaminants down to 0.0001 microns leaving behind only pure water.

A fine GAC filter takes the fifth stage and where the water from the RO tank is further polished to remove any residual contaminants from the tank.

Restoration of Lost Minerals

After going through the initial 5-stage RO filtration process, the RCC7AK includes a 6th stage which consists of an alkaline remineralization filter.

The standard 5 stages produce clean, pure water with all the contaminants removed as well as the few helpful minerals present in the water.

This 6th stage is a big plus as the alkaline filter restores the healthy minerals lost due to the RO process. The AK filter features red mineral stones which add back calcium and other essential minerals such as magnesium and potassium.

The filter also has a calcite portion that helps raise the pH levels of the RO water hence creating a much natural alkaline balance in the water.

Therefore, you not only get the benefit of drinking clean, purified water but you are also assured of getting some healthy minerals as well and a better, more natural taste.

RO water is so pure and as such it often tastes unnatural, but with this alkaline filter in place, your water will certainly taste much better.

Furthermore, the filter is made up of only natural mineral stones that serve as the filtration media hence your body will have no problem absorbing the restored minerals directly.

Filtration Capacity

The filtration capacity of RO membrane of this iSpring RCC7AK model is also quite decent for an under-sink residential RO system.

It’s capable of producing up to 75 gallons of filtered water a day which is sufficient to handle the water needs of small to medium-sized families whether it’s drinking or cooking.

Moreover, the system is relatively efficient as for each gallon of pure water produced, it wastes only 2 gallons which is really a mean feat for most filtration systems.


  • Efficient filtration process ensures crisp, clean, drinking water
  • Restores healthy minerals to the water and improves its pH balance
  • Decent filtration capacity and pure to wastewater ratio
  • Durable stainless steel construction 
  • Easy installation with a convenient noise-free operation
  • Backed by one year warranty plus a one-year money-back guarantee


  • That automatic shut off valve seems a bit flimsy
  • May need some DIY skills for easy installation

Price & Rating

ProductiSpring RCC7AK 6-Stage Reverse Osmosis System
Rating4.6 out of 5 stars (More than 1970 reviews)
Recommended price198 USD (Check the latest price at

Read moreiSpring RCC7AK 6-Stage Reverse Osmosis System

APEC Water Essence ROES PH75 Reverse Osmosis System

The second spot in our top APEC essence series RO systems is the ROES-PH75 model. This unit is quite identical to the ROES-50 above, but APEC has made two major updates.

The APEC ROES-PH75 comes with an increased water production capacity and an additional remineralization stage which are big improvements that greatly boost its overall performance.


  • Produce 75 Gallons Per Day
  • More balanced alkaline water
  • Remove 99.99% of chlorine and chloramines

Read Now:

Filtration Process

With the addition of a remineralization filter, the ROES-PH75 offers 6 stages of filtration which includes the same standard 5 stages of the APEC ROES-50.

At the 1st stage is a polypropylene sediment pre-filter which traps all particles larger than 5 microns including silt, dust, rust, and sand particles that might accumulate and clog the other pre-filters and RO membrane.

The 2nd and 3rd stages make use of the super-efficient activated carbon block filters made from coconut shell. These filters together absorb and remove 99.99% of chlorine and chloramines in the water.

They as well remove bad tastes, odors, organic contaminants, VOCs and other common chemicals like pesticides and herbicides thereby improving the smell and taste of the water.

At the heart of the ROES-PH75 system is the 0.0001-micron TFC RO membrane which filters out 99.9% of all the possible contaminants remaining in the water from total dissolved solids (TDS) to microorganisms and other impurities like lead, arsenic, fluoride, radium, and chromium leaving only pure water to pass through.

The 5th stage applies an activated carbon filter also made from coconut shell which gives the filtered water a finishing touch by removing any residual tastes and odors picked up from the RO tank.

6th Stage – Alkaline Filter

The filtered water from the 5th stage is finally passed through the last stage which comprises a calcium mineral cartridge that adds high-purity calcium carbonate into the RO water. 

The calcium carbonate effectively neutralizes the acidity of the filtered water and increases the pH level by about 1 to 1.5 resulting in a more balanced alkaline water.

The pH level of the final water will, however, vary based on the initial pH levels of the feed water and its composition. Nonetheless, with the alkaline filter in place, you are guaranteed to get purified alkaline water that tastes much better than plain RO water.

Filtration Capacity and Efficiency

Besides the addition of the alkaline filter, the RO membrane of the ROES-PH75 is an upgrade from that of the ROES-50 as it offers a higher water output.

It can deliver up to 75 gallons per day at 60 psi pressure which is enough to meet the needs of small to large families that desire a high water production rate.

The storage tank can hold 3.2 gallons of water which is a good capacity that will help keep your water supply constant for most parts.

Like the ROES-50, the APEC ROES-PH75 expels 3 gallons of wastewater for each gallon of clean water produced which is not the best ratio out there but it does ensure a high rejection rate and performance compared to systems with 1:1 or 1:2 ratio.


  • Removes all possible contaminants in the water
  • Alkaline filter helps raise the pH level and improves the taste
  • High water production rate at 75 gallons of pure water per day
  • Designed for easy DIY installation and low maintenance
  • Comes with 1-year limited warranty and filters are long-lasting


  • Wastewater to pure water ratio of 3:1 which is just above average
  • Slightly slow filling as it takes about an hour to fill the tank once empty

Price & Rating

ProductAPEC Water Essence ROES PH75 Reverse Osmosis System
BrandAPEC Water
Rating4.7 out of 5 stars (More than 885 reviews)
Recommended price230 USD (Check the latest price at

Read moreAPEC Water Essence ROES PH75 Reverse Osmosis System

APEC Water ROES-PHUV75 Reverse Osmosis System

The ROES-PHUV75 is one of APEC’s high caliber models within its Essence series providing a comprehensive filtration process that guarantees the purest water possible.


  • Produce 75 Gallons Per Day
  • More balanced alkaline water
  • Remove 99.99% of chlorine and chloramines

Read Now:

The unit is amongst the three versions of the APEC Essence ROES-UV75 model which only differs a little bit in terms of features. The first version is the ROES-UV75 itself with a 6-stage filtration process featuring a UV light filter.

The second version is the ROES-PHUV75-SS with a 7-stage filtration process featuring a PH filter and stainless steel UV light filter.

The third version is a variant of the ROES-PHUV75 which equally has a 7-stage filtration process that features a PH filter and a white UV light filter which is slightly different from the stainless steel UV light filter in the ROES-PHUV75-SS version.

In this review, we look at the second version which is the ROES-PHUV75 model with a stainless steel UV light filter.

Filtration Process

As I mentioned earlier, the APEC Essence ROES-PHUV75 is a comprehensive RO system equipped with 7 filtration stages that deliver super contaminant rejection rates and reliable performance.

The 1st stage of the unit consists of a polypropylene sediment filter which eliminates sand, silt, dust, rust and other particles down to 5 microns.

The 2nd and 3rd stages are the same quality coconut shell carbon block filters which effectively absorb and get rid of almost all the chlorine, chloramines, VOCs and chemicals that lead to unpleasant tastes, odors, colors and cloudiness in the water.

A high rejection TFC RO membrane sits in the 4th stage and it removes all the remaining contaminants down to 0.0001 microns. It gets rid of 99.99% of the total dissolved solids (TDS) in the water and 1000+ contaminants including fluoride, radium, chromium and heavy metals. The filtered water from the TFC membrane is then delivered to the RO storage tank.

5th Stage – UV Light Sterilizer Filter

From the storage tank, the RO water is passed through a 5th stage which consists of a watertight chamber featuring a UV light sterilizer filter.

This stage is what makes ROES-PHUV75 exceptionally effective at ensuring you get purified water that’s completely free of contaminants. The UV light sterilizer contains a powerful UV lamp that emits strong UV light with a wavelength of 253.7 nanometers. 

As the water flows past the lamp, all the harmful microorganisms are exposed to the lethal germicidal UV energy of the emitted UV light.

The germicidal energy effectively attacks and destroys the genetic core (DNA) of the microorganisms stopping their ability to reproduce, and ultimately causing them to die completely.

The best part is that unlike ordinary UV sterilizer filters, this one features a stainless steel interior. It reflects the UV light evenly throughout the chamber hence facilitating the highest UV coverage possible.

Therefore, no microorganism gets to escape the lethal germicidal energy from the UV light. The filter will kill up to 99.99% of all the harmful microorganisms in the RO water from bacteria to viruses to cysts and other microbial pathogens.

In addition, the filter uses an all-natural process. It doesn’t change the taste or composition of the water in any way.

6th Stage Post-Carbon Filter  

From the UV light filter, the water passes through the 6th stage where it’s further refined by an advanced coconut shell carbon filter that clears any possible residual chlorine and taste from the tank.

7th Stage Alkaline Filter

The final stage in the ROES-PHUV75 RO system is APEC’s calcium mineral cartridge which is an alkaline re-mineralizing filter and it adds calcium carbonate into the RO water thereby raising its pH level. It increases the pH value by 1 to 1.5.

The outcome of combining these 7 highly-effective RO filtration stages is total contaminant-free purified water with much-improved alkalinity and great taste.

Filtration Capacity and Efficiency

The production rate of the ROES-PHUV75 is 75 gallons per day which is the same as the APEC ROES-PH75 and makes it an ideal choice for small to large families.

A 4-gallon storage tank is included with the unit and it can hold up to 3.2 gallons of water which is also a good capacity that should suit the needs of most households.

The unit releases 3 gallons of wastewater for every gallon of pure water it delivers, so it falls a little short with regards to filtration efficiency. But again this tells you how thorough the filtration process is despite the amount of water wasted being relatively high.

Installation and Maintenance

Installing the ROES-PHUV75 may not pose a lot of difficulties with some basic DIY skills. It comes quick connection fittings and all the tubing are colored to enable fast and easy installation and maintenance.

There’s a detailed manual to guide you throughout and you can even refer to several videos on YouTube to help you out if you get stuck.

The filters are really durable and this is one of the things that set apart APEC’s RO systems from the rest. The prefilters and the 7th stage UV filter will last up to 12 months while the membrane, post-carbon filter, and the alkaline filter can go for up to 2 to 4 years.

To sum it all, the APEC ROES-PHUV75 is a system designed to deal with highly contaminated water especially where there are concerns about possible microbial contamination. It will effectively eliminate all contaminants in your water and give it a great, natural taste.


  • Fights off all kinds of contamination
  • UV light filter helps kill harmful microorganisms
  • Raises the pH level of the water and enhances its taste
  • Delivers 75 gallons per day ideal for small to large families
  • Easy to install and the filters are durable


  • Wastes 3 gallons of water to produce a gallon of pure water

Read moreAPEC Water ROES-PHUV75 Reverse Osmosis System

iSpring RCC7 Reverse Osmosis System Review

Our first top pick is the iSpring RCC7 RO system. This is one of the best-selling RO products from iSpring.

iSpring RCC7 reverse osmosis system is unequaled in performance, quality, and durability. This RO system has a 5-stage filtration that removes over 1000+ different kinds of contaminants and it features 75 GPD.

Read Now:

It’s simple and affordable but a very reliable and efficient system that’s more than capable of removing all kinds of contaminants in the water.

Filtration Process and Stages

The RCC7 features an effective 5-stage RO filtration process which does so well to produce very clean and pure final water that’s safer and healthier to drink.

The first batch of filters in the system are three carbon-based pre-filters that make up the first three stages.

The first stage is the sediment filter which is a high capacity polypropylene filter that removes all sediments and silt in the water down to 5 microns.

The second stage is made up of a 5-micron granular activated carbon (GAC) filter which is quite effective at trapping large contaminants and chemicals like chlorine and chloramines as well as removing microorganisms present in water.

All the particles, microorganisms and chlorine that leaked through the second stage GAC filter are trapped by the CTO carbon filter in the third stage.

These three pre-filters are amongst the best you will find in the market. They perform so well with regards to eliminating most of the contaminants, chemicals, and microorganisms present in the water which allows the RO membrane to function at its maximum efficiency.

The membrane itself it’s a thin film composite filter that makes up the fourth stage of this iSpring’s RCC7 filtration system.

It’s very capable of removing contaminants down to 0.0001 microns which is so small to allow only water molecules to squeeze through while stopping up to 99.99% of up to 1,000 different contaminants.

Virtually nothing else will be able to pass through. It will completely remove all the harmful contaminants that often appear in well and municipal water including chlorine, dissolved solids, arsenic, bacteria, and viruses.

The final stage consists of a fine GAC post-filter which does the final polishing of the water by removing any other TDS or contaminants in the water from the RO tank before it’s delivered to the faucet.

The five stages of the systems progressively remove contaminants, cleaning and purifying the water to improve its quality and taste. 

Filtration Capacity

The membrane of the RCC7 also has a high throughput which big thumps up. It’s capable of delivering up to 75 gallons of purified water every day which is sufficient capacity for nearly any family size even large families.

For every gallon of purified water produced, the system wastes around 3 gallons although it may vary depending on the quality and pressure and of your feed water. However, this average ratio you will find in most standard RO systems.

Installation and Maintenance

The system comes with quick-fitting connectors and everything that you need including all the parts from the storage tank to the faucet as well as all the mounting hardware and clear, well-organised instructions.

So, installation is pretty much straightforward if you are a very handy person or have some basic DIY skills. The system requires very little maintenance too as there are no moving parts.

The pre-filters have a service life of 6 months before requiring replacement while the post-carbon filter needs to be replaced every year. The membrane, on the other hand, will go for up to 2 to 3 years before requiring replacement.

Furthermore, the first stage filter (sediment filter) has a clear-see through housing which facilitates an easy way to inspect the condition of the filter and know when it’s time to change it before a problem occurs.

The only setback we noted about this system is that the O-rings are somewhat thin and look a bit flimsy. Even so, it’s not really a deal-breaker as it can last long enough before you can change it for much better quality.

All the other components and parts are of great quality. The tank is made of steel and the construction of the main RO unit is sturdy which makes it very durable. You will also not hear any sound as the system is in operation. It’s super quiet.


  • An effective 5-stage filtration process
  • Removes up to 99.99% of all contaminants
  • Can deliver 75 gallons of pure water per day
  • Has quick-connect fittings for easy DIY installation
  • See-through first stage filter housing for easy inspection
  • The filters and membrane have a decent service life
  • Comes with a 1-year warranty and lifetime support


  • O-ring is quite thin and somewhat flimsy
  • The wastewater ratio is relatively high

Read moreiSpring RCC7 Reverse Osmosis System Review