What are the different types of water filters?
Posted on July 12, 2011
There are a whole host of water filters available in the market today. What you need to consider before purchasing one is its effectiveness and what it.s going to cost you. Water filters offer different features and also protect from different contaminants. Virtually all of the water filters sold today require periodic filter replacements, these can cost anywhere from $10 to $300. Some systems may also require professional installation which costs more.
Below are some of the different types of water filters available today:
- Carafe filters
There are a few models that do an excellent job in removing lead and chloroform without sacrificing cartridge life or reducing flow rate. Others are slow and prone to clogging and have a short filter life. A carafe in the refrigerator might be sufficient for one or two people, but not for a family of four or more that consumes several gallons of water every day.
- Faucet-mounted filters
These are easy to install and are a good choice for filtering drinking and cooking water. You simply unscrew the aerator from the threaded tip of the faucet and screw on the filter. Faucet-mounted filters let you switch between filtered and unfiltered water which is useful but on the downside they slow the water flow, and they don’t fit on faucets of all sizes.
- Countertop filters
Countertop filters screw onto the faucet after you remove the aerator. These filters let you clean large quantities of water without modifying the plumbing, and are less likely to clog up than carafe or faucet-mounted filters. They can however clutter a countertop and they don’t always fit all faucets.
- Under-sink filters
Like countertop filters, these too can filter tons of water. But unlike cluttering the counter, they take up space from the cabinet beneath the sink instead. These filters require professional plumbing and drilling a hole for the dispenser through the sink.
- Reverse-osmosis filters
These filters use pressure to pass water through a semi-permeable membrane. They remove a wide range of contaminants, including dissolved solids, and are also the only type of filters certified to remove arsenic. However they must be sanitized with bleach periodically. These filters are extremely slow, take up a lot of space and create 3 to 5 gallons of waste water for every gallon of purified water.
- Whole-house filters
These filters have proven to be an inexpensive way to remove sediment, rust, and with some models even chlorine. These filters have long cartridge lives which reduce replacement costs. Most whole-house filters however aren’t designed to remove many other contaminants such as cysts, metals, and volatile organic compounds. They require professional plumbing changes in order to be installed but not at the sink or faucet.