I had added the big water carboy into the vacuum system, because if you have a leak then, in theory, the big vacuum reservoir will maintain the negative pressure. Two things happened. First, I did have a leak that I could never find. And second, when I really vacuumed the system hard, carboy imploded. I was worried about all of this and had a a back-up plan. I had heard of people using aquarium pumps as continous vacuum pumps for making model airplane wings. It seemed super weak, and unlikely to work that well, but I had scouted around on Amazon and found a cheap, semi-industrial aquarium pump for around $30. I hooked it up and voila! Continous vacuum! At this point it didn't matter that I had a little leak somewhere, because the pump created a continuous vacuum. It worked awesome, although it made a ton of noise that you could hear from any point in my house, even though it was in the basement.