If cost is a factor for your topper. My approach was very cheap
I went to the store and got industrial grade velcro and a new screen material for a window. I applied the velcro around my whole tank, then carefully used adheasive to apply the screen to it, cut holes just big enough for my HOB overflow. I cut a big hole in the middle and made a flip open cover in the middle out of excess screen. Its crude, but essentially escape proof for the eel. Any wires I need to run into the tank I dont cut holes I just run them inbetween the velcro layers.
As for feeding, my snowflake has been on silversides since day 1, and also.. is a garberator, I feed him every other day cause well, he doesnt just take it, he seeks it out and demands it. If he wont take the silverside right away, rub it up against the live rock and break the tissue and hold it in front of him.. once he catches wiff of the meat, he will be all over it im sure.. and start small, mine doesnt care who catches and bags my silversides, but Hikari seems to give you the best quality ones that ive noticed. The only thing in my tank that gets krill is my puffer, and that is just the warm up to his silversides or clams.
As for the hideout, play god a little here, and wait with the food near your pipes, and he will start to know that is where you feed him.. and maybe just start setting up camp there.
Aggression, some snowflakes are very aggressive, but it seems to vary from eel to eel.. some people have no issues.. mine seems to re-kill everything I feed him, and slams it around and tries to break its neck over and over. So my little guy has some violence issues. I had a lion for awhile, and the snowflake never liked him, and even attacked the lion when he got too close..
