Hi we keep both and have a pond - it's a big mill pond with an in and out flow so keeps itself clean. We did make a pond in our previous place approx. 3m x 1.5m which we had to bucket the water out each month and replace it via a hose but it became a chore to be honest, you're better with something smaller you can pick up and chuck out the water. If you don't have an in and out flow then keep a bucket of water filled to the brim you can replace daily which they will drink from and douse themselves for cleaning, saves disease. If you can secure an in and out from a burn or weir all the better.
As for plants (finally on to your topic sorry) I'm not sure about cleaning, but you will have to wait until whatever plants you put in are a big size or the geese will just eat them down to the quick. You'd have to put them in some kind of planters chicken wired off initially until they get established - tall plants are less likely to be eaten by geese but they will eat the juicy shoots coming in the following year. Some duck species will eat too.
I know people use barley straw bales in ponds to keep them from becoming septic tank like. Hope there's some help in all that!