[mjs500doo]

Also you'd be surprised at what the biggest Roos can get in/out of. Make the opening large enough to accommodate your Roos. Better slightly larger than too small.

Your hens will all have their favorite nesting box, I personally recommend 1 box per 5 hens to be on the safe side. My biggest hen prefers the box that is on the tippidy top and has to fly from the roost over to the perch then hop into the box. But whatever! She loves that spot.

As for guinea introduction, always introduce new fowl after quarantine at night. When I first got guineas, I had one feral hen creep into the coop with my chicken flock and I bought her a lavender boyfriend. He was more scared of the chickens than they were of him! After a while he did start "chasing" the flock around when they got too close to "his" area and grabbing tails, but all guineas grab their tails for some reason. I purchased a white hen shortly after, she was a touch meaner, but when you introduce a guinea to a flock of chickens your size I would not worry about a thing. If you had like one hen I would be more nervous about it, but they'll be fine!

 

[mjs500doo]

You're right on with the roosters. With your number, you will need that many if you want fertile eggs.

As for guineas, have you considered 2 females/1 male? In my experience our females are way less nervous. They lay (in early summer of course) in the nesting boxes with the hens, they tend to stick closer to home, and they're better companions to the chickens, as males tend to be a bit more "mean"/"bully". Btw I love royal purple!

As for nesting boxes, 1 foot off the ground is more than supple for JG and RIR. Are you housing them together? Just curious what you'd do come time for egg collection. The Roos will develop an anarchy of hens, and I can promise you the RIR Roos will have some JG hens and vice versa. Our roosts are 3-4 feet up in the air, we have ladder rungs and dowels. The big fat JG, Orp, and Maran hens have no problem getting up on the top rungs.