Activated carbon filters represent one of the most efficient and cost-effective ways to purify air as well as water. Air purification is important in hydroponics as well as good, clean water in maintaining hydroponic systems. You'll find many different types of systems available at stores and websites that sell hydroponic supplies, but you'll want a good supply, as activated carbon filters require periodic changing.

The Importance of Carbon Air Filters

Although "hydroponics" literally means "water gardening," air purification is an important component. One of the challenges maintaining indoor hydroponic systems and indoor gardens is eliminating the many airborne contaminants that can cause your plants to sicken and even die. It's a good idea to have a blower of some kind that brings in plenty of fresh air to the space, but carbon filters are necessary in order to remove various potential toxins from the environment as well.

There's another important reason why when engaging in activities related to indoor horticulture, carbon filters are important, and that is to keep odors at a minimum.

Types of Carbon Air Filters

There are several types of carbon filters available:

• Powdered activated carbon (PAC)

• Granulated activated carbon (GAC)

• Extruded activated carbon (EAC)

• Impregnated carbon

• Polymers coated carbon

• Activated carbon fiber

Each of these has a specific use, not all of which are appropriate for hydroponic systems and indoor gardens. Indoor air filters are of the GAC type. Used on U.S. Navy submarines, granulated activated carbon filters contain a form of that element of which the granules are relatively larger than that found in powdered activated carbon air filters.

How Do Carbon Filters Work?

It is not possible to see the process by which activated carbon purifies air and water, nor even under any but the most powerful electron microscope. Carbon is activated by treating charcoal with oxygen, which opens up millions of "micropores" in the surface of the granules on the atomic level. This provides a relatively huge surface in relation to size - up to 2,000 square meters per gram! Because of this surface area, organic chemicals that have a tendency to bond to carbon are virtually unable to pass through and are trapped.

By the way, carbon air filters are not effective when it comes to inorganic chemicals (the exception being chlorine, which is why activated carbon is good for water treatment). However, chances are that your plants won't be producing sodium or any nitrates, and it's unlikely to enter your indoor garden from the outside.

Replace Your Carbon Air Filters as Recommended

There is a limit to how much in the way of organic contaminants activated carbon filters can absorb; therefore, they need to be changed regularly. You can extend the life of your carbon filters by using them in combination with HEPA filters.