A) don't get a feeding tub. It causes stress and increases risk of a bite. Its really not nexessary. They learn what's food and when it's coming fast. And we have yet to have one unable to differentiate between food and hand
B) small amounts if ingestion are fine. Snakes often get mouthfuls of dirt or grass or what not in the wild
C) I also live where live rats are illegal so what we used to do us the at room temp and then just wet the head. Dangle high. Snake strikes up and gets all the wet in its mouth right away.
D) we are in tubs now....we have 22 so its much more feasible for us. We kept on blank newspaper at the end of our tank days because it was easier...but its not pretty. Any dirt based substrate should be fine if ingested in small amounts so it will look nicer.
Sent from my LG-H831 using Tapatalk