Need Duck Advice! Winter is coming.... what do I do with the ducks?

We've had our pekin ducks, Harry and Sally since May (they were young, maybe 2 months old when we got them).

They have been cohabiting with our laying hens fairly well, although my male duck will NOT leave the hens alone and both ducks are really bossy with the hens.
They do go into the coop each night when the hens do but they are so messy with the food and water.

I thought it was fine to have them all together, but now I'm wondering if I need to keep them separated from the hens, or ?? Some of my hens have lost a ton of feathers on their backs and necks from Harry bothering them and I think it's affecting our egg cycles.

I don't really want to get rid of the ducks, we love them, and the eggs are great, but... they make a huge mess and they stink up everything and they put mud in the hens water, and their pool/pond is disgusting and needs constant cleaning, and I have no idea how to properly care for them during winter- I do not want to bring their pool into the coop- and have no idea how to keep that clean during our harsh winters here in Canada...

Keeping them and separating them from the flock would mean another fence build, which I'm not sure we are up to doing just now.


I need Duck advice.

Thanks