I have 16 ducks on my .62 acre pond.

I tried rounding them up at night into a pen, but they quickly stopped letting me do that they just stay out in the middle. My pond is 1 year old and has had FA on alot last year it totally covered the pond. This year I had FA all the way around the pond about 10 to 15ft from the banks. The ducks have totally eaten the agea up.

I like that they are keeping the agea down but I'm concerned about them pooping too much and degrading water quality. I try to feed them away from the pond but they rarly leave the pond, they may wonder further from the pond as they get older. My pond gets alot of run off, with normall rain it gets enough to fill the pond at least 3 times a year.

Do I have a potentail problem with these ducks?

Also do duck eats tadpoles, frog and frog eggs?
I've seen a few bullfrog tadpoles floating toward the suface after the duck have swam by, I think they a trying to eat them, but not able to get them down.