25-50 ducks on a quarter acre BOW is a lot. I do agree with you on battling mother nature...her goal is to fill in your new pond. I'm thinking ducks and excessive vegetation would be an ideal first step towards that goal. My ponds are over 40 years old, and I still deal with invasive plants, semantics aside.

"Forget pounds and ounces, I'm figuring displacement!"

If we accept that: MBG(+)FGSF(=)HBG(F1)
And we surmise that: BG(>)HBG(F1) while GSF(<)HBG(F1)
Would it hold true that: HBG(F1)(+)AM500(x)q.d.(=)1.5lbGRWT?
PB answer: It depends.