I did carpet cleaning and build HUGE cage for Romeo and Belle to live together.
I made a perfect hay rack that I don’t have to refill everyday (just once a week) My rabbits have no problem to access the hay rack.
Belle didn’t poop all over places anymore. I found a huge puppy dog litter box that rabbits can easy hop in and out. Romeo and Belle love it already.
I build second floor in cage for Romeo to eat pellets or leftover vegetables. (Belle will eat all of them within few minutes but Romeo didn’t eat all of them within few minutes. He will eat some of them every other hour or two.) Belle didn’t jump on second floor for about a month.
NOW, Belle can jump on second floor to steal Romeo’s pellets and vegetables 
I ran out of ideas to stop Belle from stealing Romeo’s food. I don’t want Belle to become overweight or Romeo become too thin. (Romeo looks like he lost his fat, not fat as “fat” just healthy fat)
I thought to reduce their pellets consume to 1/8 cup a day. Is that really okay for them? I’m okay with it but I don’t feel confident with it because it may not give enough nutrition (Carbs, sugar, “heathy fat” ) to my rabbits since I don’t give them treats. I gave them treats like once in every 3 months. ( My rabbits normally eat 1/4 cup of pellets a day since I adopted them)
What about vegetables? Sometimes I’m too tired to stay in rabbit’s room and need to go bed early so I can get up 5:30 am in morning to prepare vegan food before I go to work at 7 am. So I won’t able to watch Belle and stop her from eating Romeo’s food. Right now, I have two jobs for this summer only and dont want to feel extra stress to worry about will Romeo get enough food or afraid Belle will become overweight.
Thank you for reading and helping me out if you leave comments.