Review on Discover the Majestic Pen-Plax RR693 🏰 Medieval Castle of Germany Aquarium Ornament - Small by Dawn Adams

The lock is beautiful and the details are cute, but it is NOT small. If your tank holds less than 10 gallons, it is too big for your tank. I keep it in a 20 gallon tank that is 30 inches long and occupies a good 1/3 the length of the tank. If you have a Betta or other thin finned fish in your tank you will need to file down the sharp edges, feel around the opening and file down the inside and outside of the lock and any sharp points you feel if you like Don't do this, the fish may get caught and tear off the fin. The tower is hollow and fairly large fish can get stuck in it, I solved this problem by putting a piece of filter sponge inside.