pond filter requirements

Talking to local pond builder who only uses an 'undergravel' type filte in
his ponds - like a large version of an aquarium setup. Does this sound a
bit wacky?

I tried an undergravel filter in a 150 gallon kiddy pool and it didn't work
all that well. It was a good bio-filter but didn't do much as a mechanical
filter.

/ONLY/ an undergravel filter is a bad idea, in the long run. Particulates
will accumulate in the filter. Some sort of mechanical prefilter would be
a good idea here.

For a larger pond, a settling tank.

For the larger pond, and the smaller pond, a skimmer with a good filter
screen.

There are many other, more expensive options. Know thyself. Extra
money for a low maintenance device is well spent if you are not going
to really maintain.

Not to forget: the veggie filter. Essentially just a separate tank area,
heavily overplanted with fast growing water weeds. Something that is
invasive in your area is what you want, if you can legally get it.

When the stuff fully grows out, cull it. It's a waste removal system
of sorts.

C//