undersink 4 STAGE FREQUENTLY asked questions 

What are the different stages in Bluonics 4 Stage undersink filter?

Stage 1: Standard Size 2.5”x 10” Sediment Filter. Filters sediment particles such as silt, sand, rust, dirt, and other undissolved particles.

Stage 2: Standard Size 2.5”x 10” Granulated Activated Carbon (GAC). Adsorbs and removes bad taste and odors. Also a large variety of organic contaminants such as chlorine and chemicals linked to cancer, like pesticides, herbicides, insecticides, Trihalomethanes, Benzene and many volatile organic compounds such as VOC's, PCB's, MTBE's along with hundreds of other chemicals and contaminants that may be present in our water.

Stage 3: Standard Size 2.5”x 10” Carbon Block Filter. Removes chlorine, bad taste and odor, organic solvents and organic chemicals that contribute to bad taste and odor.

Stage 4: Ultra Violet Light. Treats harmful Bacteria, E Coli, Viruses Fungi, Algae most microorganisms including 

cryptosporidium and giardia, and many other contaminants.


 I am building an RV that we will use in a long trip through South America, and possibly, we will use water from rivers and lakes to drink- what do you recommend to filter and purify the water? Filters, light, something else? Important, I have limited space for fresh water so I cannot waste water on the drain.

For your situation, Bluonics 4 Stage , UV Ultraviolet Light Drinking Water Filter System Under Sink / Counter Purifiers is the right filter unit for you.

Many people use this in their RV, boat or mobile homes.

Can the bluonics Under sink 4 Stage with uv system be used with the current faucet in my kitchen? If so, do I need to buy an attachment for it to work?

The pressure you get from Bluonics 4 Stage, won't be enough for the kitchen faucet. The amount of water available to use, is the amount of water the UV light can disinfect which is 0.5- 1 Gallon per minute. Your kitchen faucet typically dispenses water at a rate of about 2 gallons per minute. In the real world you will frequently run out of water.

 I installed the 4 stage system and the PPM or TDS did not changed.

This system is not intended to reduce the PPM, because it does not have a reverse osmosis membrane. To reduce your PPM you will need a reverse osmosis system.