I haven't thought about freezing. Probably only as long as it does on the shelf. After awhile it will get freezer burnt and be useless. Once openned fish flakes are only good for about 6 months. It starts going stale immediately but after about 6 months it has lost pretty much all nutritional value. It depends on the quality of the food though. The mass manufactured foods like Tetra generally last less time because they sit in warehouses for such a long time generally. Smaller market foods generally last a little longer because they generally go to specialty stores instead of chainstores like Petco, Petsmart, etc and the turn over is generally faster.
