Now that's a good point Mickey.
Mr.Russell,I would recommend a look at the Nexus range from
www.evolutionaqua.com/ if you want to see a real ground up koi filter design.It's not the only kind, but it is right up there with the best and commands quite a following already due to it's performance and ease of use.
I would also recommend a read of
http://www.koicymru.co.uk/construct.htm for a perspective on hobbiest koipond design.A very informative site.
You wanted to learn.
