i did have one of those sea like wallpapers on the back of my tank that you can buy at the pet store ever since i got Flame. I never had an issue with him flaring at it before until today. My last glofish died in my 5gallon tank, so i tore it down and i decided to move Flame on my nightstand where my old tank was, just so he was closer to me and i could keep an eye on him better. Well, a little bit after the move I noticed him flaring at the wallpaper, so i took it down. Well, i don't like my tank without so i tried to stick a piece of black paper behind it, thinking well it's black and not too bright it shouldn't bug him. he flared at that too.
Any advice on what in the world i should do.

this is what it looked like before. and i absolutely LOVED it.

that is what the tank looks lilke now without anything...it's gross looking
please help (:
also, any new ways to decorate my tank. some objects from around the house. best kind of gravel, no gravel? i wanna switch things up.