It was hard to make, it took me a week to get it set up, using splash potions of weakness, and golden apples, not to mention moving them all into their new homes using mine carts.
That's too bad that they don't spawn, I wouldn't have built it had I known.
Farming Eggs, = way easy, 35$ per 9 stacks, also a passive income, easy to build and make,, which can buy anything including iron. Iron can't actually buy anything, unless trading with other players.
I suggest that you start farming eggs, seeing that it's way easier to get iron in that way.
See, iron is perhaps the most valueable material in skyblock when is comes to constructing stuff. That makes it a material that should be hard to get on a limited resource server like skyblock.
Also, you could have asked any skyblock staff before building your farm and they would've told you that you can't amke them.
On a second note i'd like to add that if you choose to overdo your chickenmachine(s) it will lag you like crazy and chickens might spew out if it....
Simple chicken machines can be set up without escapees regardless of the amount of chickens inside. They do not require any non-renewable resources. I set one up in 15 minutes or so with a single output point, very effective!