What type of cement should I use what is waterproof? and What type of glue should I use?
Very good job on the backround. Very natural looking rock wall. If I may inquire, what type of fish are you going to put in the tank?
Check out Fosters Smith aquarium catalog. There are special glues used for marine application. I don't think the the foam or cement will work. The fish will want to eat the foam and you will have to use a special type of cement that is non toxic. Try creating a rock wall with the marine glue. In addition you can make an interesting back drop that is placed behind the glass. Remember what ever you place in the tank will have to be removable so you can clean it. Fish dirt will collect in those areas with no filtration or current.
