A pond filter is one of the most important components for your pond, without one your pond water would get really mucky. The kind you need depends on its size and whether or not you have any fish.
Filters come in different sizes and varieties. You can get external, submersible, bio and others. They range in price from 40 or 50 dollars, all the way up above $1500.00 and more.
Having a pond filter is not the only thing you need to have nice clear water. You also need a UV filter and plenty of pond plants, especially in the summer when it gets really warm. The three components above, all work together to give you nice clear water.
An important aspect of having a pond filter is having an area in the filter that can capture and grow good bacteria to help maintain the waters proper balance. This is where pond filter media comes into play. The bigger the total area that can capture and grow this good bacterium, the better off you are. Pond filters use different things in their filters to promote this bacteria, from sponge like material, to bio balls, and a polyester knit material, which I use, and also sell if your interested.
This should give you a better idea about the importance of a pond filter.
Robert Dorrance has had a pond for the last eight years and would like to share his experiences with you. Find out more at http://www.Backyard-Pond-Guide.com