Making the skimmer box is not a problem, and the use of the marine plywood
would probably work well. The problem is that you want a weir that is
floating or spring loaded so that it is pushed over by the water trying to
get into the box, making a very thin layer of water be skimmed. As the
water level in the pond fluctuates, the weir needs to be able to move with
the water level. A thick layer of water entering the skimmer will not
produce the desired skimming action.
--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html
"daryl wilde" wrote in message
...
The cost of the skimmer and filter box are expensive ~$500 or more. Has
anyone seen plans to build one? Any special concerns??

Thinking of using either external quality (CDX) or marine grade plywood
and
then covering with liner......comments. Expect the pond to be 6 ft x 8 ft
or so and 18-24in deep.

Thanks Daryl