Food
In order to be self supporting in space, you have to grow your own food because you use too much for it to be rocketed from Earth. In a rotating space station, food would probably be grown in the wheels closer to the center because the lower gravity would encourage plant growth. Insted of using a biosphere copy, you should just use intensive agriculture because you can use all your space and every square foot is growing your dinner. You will have to use lights with a spectrum similar to that of the sun. For larger plants, artificial wind should be added in order to harden the wood. For a higher growth rate, raised carbon dioxide rates seem to help although it seems to lower calcium. There are two bases for the plants which might be used. One would simply be enriched soil with pipes running through it to release water. The enriching microbes may eat much of the oxygen so the agricultural areas should be isolated from the rest of the station. Here is an illustration of this method. The second method grows the plant in a gravely base similar to kitty litter. Nutritionally enriched water is continually flowed through this, providing food to the plant. Here is an illustration of another method. Along with your veggies, meat is an important part of a healthy diet. In space where room is limited, you must be very selective about which animals you choose to keep. Cattle take up too much room and so should only be added after many spaceplexes have become self-supported and such luxuries can be afforded. Insted, rabbits, chickens, and goats would be the animals of choice. A family of rabbits can live comfortably in a 3x3 foot hutch. And given their ledgendary ability to reproduce quickly, these could easily supply all meat needed. Chickens can also live in small pens living on waste grain. Chickens can supply eggs and round out the meat selection. Goats need slightly more space, yet supply butter, cheese, milk, and other dairy products. They also supply meat when slaughtered, but this should only be done when they cease to supply milk.