Do you want to complement your beautiful Betta fish? Why not fill your aquarium with the awe-inspiring Betta tank decorations?Betta fish are some of the most colorful aquarium fish out there, coming in all colors of the rainbow. Not only do they have brilliant colors, but they have beautiful flowing fins. The primary problem with betta fish is that the males of the species tend to be very territorial and aggressive. This makes it a challenge to keep them with other aquarium fish.