A painted tank with beach sand.
Just make sure the tank is clean. I clean with acetone. If done well you'll easily get 5 to 10 years provided the adhesion was good and you don't get a lot of leaks drips and salt creep. Make sure the glass is clean dry amd warm. Occasionally you get a tank that peels but its few and easy to fix.
Pretend you're painting a car thin even multiple coats without drips and it will last for years.
