"Iain Miller" writes:

I would think the pump fed is easier to set up

Why? Same plumbing.

& is not sensitive to water
levels in the pond

Your pond wants a constant level anyway or it looks bad
(exposed liner).

but the gravity fed seems to have the advantage of being
able to catch a lot of the cack in a settlement chamber and less pump
maintenance.

Yeah, pumping dirty water means cleaning a prefilter. Gravity fed can mean
less equipment in the pond (if you pump feed with a submersible pump) and
no need to wire the pond for electricity.

For gravity fed with an external pump, if the filter is remote the pump noise
is too.

I would only do pump fed if the filter level had to be above the pond level.

IMNSHO