Betta ornaments are an exciting way to decorate your aquarium. With something for all tastes, they are an affordable way to enhance your display using fish-safe materials suitable for coldwater and tropical set ups.. Betta tree stump cave is a natural looking ornament with places for fish and other creatures to explore and hide. This will look great in any aquarium, vivarium, or terrarium.. Approximate dimensions 16.3Cm l x 15.6Cm w x 11.5Cm h .