i would think a dwarf angel wouold be fine as long as they are not the realy small ones. as far as a yellow tank, i believe they should be in a bigger thank than a 72, but many people think that size is a good one. tell us about your hood and we can tell you how to SFEproof it. Mine right now is in an eclipse. but when he gets a little bigger he is going to my larger tank that has eggcrate on the top. I cut it so that it fits with everyitng on the back. But you can use ducct tape, justmake sure there are no holes big enough for him to fit though.