Do You Need To Seal A Chest Ice Freezer Cold Plunge?

JB Water Weld is the best way to seal a chest ice freezer.  

Some people have luck using this without a pond liner but the life of the freezer might not last very long.  You are going to want to use this product on all the seams inside the freezer before use. Here is a cold plunge guide that will help you build one for yourself. 

J-B WaterWeld is a specialized epoxy putty designed for underwater repairs. It is formulated to adhere to wet and submerged surfaces, making it ideal for fixing leaks, cracks, or holes in items such as water tanks, pipes, swimming pools, boats, and other water-related equipment. This epoxy putty can set and cure even when exposed to water, creating a durable and watertight bond.

You will also need to seal the plug with a small rubber o-ring that you can find at any hardware store.