I have no idea how long the Bio Max will last but I would imagine it would last way longer than 3 months. I have used other ceramic media in filters for years without it degrading so I doubt the media will be the problem, however that media I have used was not enclosed in a bag. I would guess the bag that Hagen puts the media in would degrade quicker then the media itself. While the bag may keep the media together and make removing it easier, I would bet it will also make it more difficult to clean. I don't usually use the Bio Max but prefer to add more sponges for my biological filtration.