I did read somewhere that Vaseline is not good to use; not that it is toxic or anything, but it does something over time. I'm sorry I can't remember the reason, but I know the advice was to use the proper filter lubricant. I think several filter manufacturers make this, I know Eheim does as I still have the tubes that came with my canisters. You can probably get this in some fish stores, or online anyway.
I've no idea if other non-aquarium products will work, or be safe.
Byron.