Raising chicks and ducklings together... w/ duck q's

[FlowerFarmer]

We recently rescued 3 baby wild mallard ducklings; they're probly just a few days old. We currently have 4 chicks who are 9 weeks old and living in their spacious coop and run. The ducklings are in the outgrown brooder in the garage. (We're lucky that we have all the chick stuff to help them)
Im preparing to raise them and possibly keep one or two to live with the chickens and range the yard with them a few hours a day. (Although Im aware they will probly fly away when they can)
Does anyone know about integrating ducks with chickens?
When do ducks feather? Fly?
Do they need duck food or will the chick food suffice?
When can I sex them? And how do I tell? Will their color change tell me anything about the sex?
Are female mallards egg layers? (I hope so)
And I have more questions about ducks living in a chicken coop...(like do I have to have a 'pool' for them inside the coop run, or can they have daily access to one in the yard?) ...... I'll start with these

Thank you!

 

[icemanchicken]

Ok im not a duck person but ill help where i can. Duck food would prob be better but i fed my ducklings chick starter for a month and they are fine. As for a pool i just used a large dog water bowl for the first few weeks. And as far as getting along, my brother has a magpie and a chocolate runner in his chicken pen and they do great.