Before the final steps of decorating and planting, I wanted to get the filter up and running. I had some materials lying around the house that I thought I could use to get started; all I need were some extra fittings and some hose from the hardware store. Below is a photo of the basic components:
From left to right, we have: (1) Some DLS, that stuff they use in air conditioning ducts; (2) A 1/2" PVC end cap, to cap off the spraybar; (3)Some stackable plastic trays, each with holes drilled in the bottom; (4)Filter media, which can be a mix of activated carbon, Bioballs(or other commercial medium), and/or gravel; (5) A spraybar, made of a piece of 1/2" PVC pipe, cut to fit the width of the bucket plus a bit more(for the elbow & nipple to attach the hose from the pump and for the end cap) and with a line of holes for the water to drip out of; and (6) a bucket; in this case, a kitty litter bucket. I drilled two holes near the top to insert the spraybar, and a bunch of holes along the bottom edge for the water to drip out back into the pond.
I put the filter media inside sections of an old pantyhose leg, and tied each one off with a knot; these "bags" were then placed in the plastic trays. I put about 1/2" of gravel in the bottom of the bucket, then placed the trays, stacked atop each other, in the bucket, with a piece of DLS on the uppermost tray:
Then I ran the spraybar thru the holes, placed the endcap on, connected the hose, and turned on the pump:
I then placed the bucket on the edge of the upper pond, so that the water draining from the bucket would fall back into the pond:
EUREKA!!! IT WORKS!
The hose from the pump was laid along the ground outside the pond and covered with stones to hide it. The pump, BTW, is a Little Giant submersible pump, rated at approximately 135 gallons per hour and can lift water in the hose to a height of eleven feet.
Now all I have to do is figure out a way to disguise the bucket...maybe hide it behind some shrubs or tall plants...