300 Gallon Fish Aquarium for sale. We used it for a beautiful Salt Water display with Sting Rays and Sharks. It is too large for our new home, so we are very reluctantly selling our prized display tank. Both the tank and the wood stand are in great condition. The price is firm. Most tanks of this size sell for 2K to 4K. You must be able to move the tank to your location. It is very heavy and will require about 3 strong people to move it.