Aquariums aren’t designed to last forever, and over time they will develop leaks. Because of this, purchasing a used aquarium has its risks and even new tanks aren’t totally immune to the problem. Fortunately, you don’t have to wait until the tank is full of water and livestock to find out you have a leaker. When buying any aquarium, be sure to leak check it prior to setting it up. Place the tank on some type of cloth that really shows wet spots, then fill it up. If there’s a leak, which may take a few days or weeks to find, the paper will show it and you can prevent the headaches of setting up a faulty aquarium only to have to tear it down.
Conversely, if you have an established aquarium that starts to leak, there’s really no other safe option other than breaking it down for repair or replacement. A leak will never go away or fix itself. It will only get worse with time, and one day you may come home to soaked carpet, a broken tank, and dead fish and corals. So, let’s play the better safe than sorry card and replace those leaking tanks.