tank looks incredible andrea! nice work. Here are my guesses on the 2 "x" plants. The one on the right is either dracaena "janet craig" or "lemon lime" hard to tell. The second I'm almost positive is dracaena "tricolor". They're both cool plants, but they like their soil to dry out a tad bit before the next watering, and a fair amount of airflow. As for the "?" plant, i can't really see it to well in the picture. It kinda looks like a snake plant (sanseveiria sp.) If it is, it should do alright in there. Leave the ivy in there til its dead. Surprisingly, ive had one type of ivy do alright for a while in a viv, although most don't do good. you never know!