As I make my Great Stuff Background for my new 55 gal Gecko tank. I was thinking of adding a cup like area to hold a plant or two for looks. I noticed a really cool looking cactus at the store the other day, and was wondering if it would be a good idea or not? However it does have the pointy things (like my technical term?). They are not as long and sharp as some cactus I have seen but they are there. I could just put Pothos in there, I just wanted something different. They wouldn't be placed in a direct path area, but I don't think I could put it completely out of the way where they would NEVER come in contact with it. Thanks!