For a Highly Efficient Biofilter for Your Garden Pond, Consider a Aquabead Filter

If you have a large koi pond, you should consider an aquabead or aquadyne filter due to the extra filtration needs of these types of garden ponds. These filters are also known as fluidised bed biofilters. Now if you have a small or medium-sized pond, this type of filter is probably overkill for your requirements.

One way to think of an Aquabead filter is the analogy of a coffee cup, where the beads in the filter take the place of coffee grounds.  The beads are suspended in a turbulent mass as pond water is continuously pumped through the filter. The beneficial bacteria are actually living on the outside surface of the beads, and as the beads thrash about in the water, they absorb ammonia, then convert that ammonia into nitrate. This large surface area allows these types of filters to work very efficiently in removing harmful chemicals from your pond water.

In some types of bead filters, there are over 600,000 beads per cubic foot of filter space.  As you can see, this is a high surface area, and allows these filters to process large amounts of pond water.

Rule of thumb for bead filters

• One cubic foot of beads are able to convert the ammonia released from one pound of 35% protein fish food daily. What this means in practice is that one cubic foot of beads can filter a pond containing 100 lbs of fish.

• Solids accumulate on the biofilm of the beads in the Aquabead filter. These solids are removed by backwashing the bead filter.

A word of warning about this type of filter …. Very small or broken beads can actually block what are called laterals inside the filter. It must be possible to remove these laterals for cleaning out if necessary.

For more on this topic, see the fish feeding article and this pond pump article.

Pond pumps

sitemap

copyright © 2005  Kent's kayak journal