I think he's talking about the tank having to grow in size with the snake. He doesn't want to have to keep throwing away tanks as the snake gets bigger.

Tanks do not insulate well, especially in cold environments. Try an actual reptile enclosure for when the snake is older, and smaller plastic tub enclosures for when the snake is small. Plastic insulates better and isn't expensive(plus you can use the tubs for storage after the snake has outgrown them).