you probably shouldn' tell people you breed rats for feeders... we kind of look down upon that. your cage looks good. I think you need one FULL level, and maybe 2 1/3 levels or something? If its a young rat you won't need ladders, plus they might be hard to make with that material. tubes are fun, if you go o home depot you can get the PVC piping. most people get the big ones to make sure ratties won't get stuck. some rats like ropes, mine don't seem very interested in them but you never know. hammocks can be made out of fabric, bandana's work well. Harlen block are good, kim's ark rescue sells it and its a great price $1.00 per pound of food, and shipping's not bad. i keep my 15 pounds in a sealed container to keep them fresh and mold free. Water, i'd suggest a glass water bottle, since plastic ones can leak easy (they bend) or rats will chew on them....ummm i don't know what else!!!