Natural Pools and Pet Ducks?

I'm curious if anyone has any experience on how well natural swimming pools (a la David Pagan Butler's technique or others) fare with a small number of ducks?

We have a two pet ducks and while we have a store-bought formed pond for them in the ground (with UV biofilter), we'd ideally love to have a more natural system, as well as having a natural look - especially if it's able to be filtered enough that it's okay for human use! Our ducks have free-range in our yard from approx. dawn-dusk and during that time they can visit our pond whenever they'd like. One of them practically lives in it during the daytime hours.

Our pond has fish as well as several adult frogs. But, with our ducks in there frequently, the electric filtration system's pads definitely clog easily as it works overtime being the only device/method for filtering and none of the solid organic matter or soft organic matter has anywhere else to go. Their solid organic matter is a mixture of store-bought poultry crumble, insects/bugs and free-range vegetation.

Do the natural pools work well with ducks? How well do they filter out organic matter?
Would a natural pool still be able to maintain cleanliness for humans with ducks present?
Would any modifications need to be put in place specifically for waterfowl or do the basic systems/techniques work for this application?

I'm completely new to researching natural pool techniques and systems.

Thank you!

Hi Alexa,
ducks are the angels of doom for a Natural Swimming Pool!...OK well I'm over dramatising.
Here are the reasons:
1) They pull up the plants in and round the pool. The plants are needed to condition the water in a Natural Swimming Pool.
2) They stir up sediments, introducing nutrients into the water. (nutrients leads to algae)
3) Their poo introduces lots more nutrients.
4) They are a health hazard albeit not a dangerous one. Swimmer's ich - cercarial dermatitis. Flatworm parasites that use both freshwater snails and waterfowl as hosts in their parasitic life cycles. On leaving the snail, they mistake swimmers for ducks and die as soon as they enter our skin. But it can cause an irritating itch.

A quack can send me into a Pavlovian response, I jump up, run out the door and shoo the wild ducks off the pools.