No offense meant, but I would not call those nano cubes. They are basicly large glasses, and nothing beyond some plants should be kept in them IMO. Now, there are some larger vessels available if you want to do something different. There are some nice tall cylinder shaped glass available at some stores. There is a member here from Germany, her user name is Ulli Bauer. She is a member of a forum called crustaforum, and has done some neat & unusual cylindrical tanks that rely on mostly sunlight. Also, anacharis kept in a tank that is warm will rot and die. If you are keeping those tanks warm I would recommend you keep an eye on it. Another thing that causes it to rot is keeping the binder/weight on them...take it off.