CHSUB
"Certified Hobby Expert"
Cost is a relative term. This is a hobby and you should not sacrifice needed money on this hobby. Anything you spend on the tank should be after the "bills" are paid - mortgage, savings, retirement, college tuition for the kids, etc etc.
Dont blow your future on the tank. Fund the tank after the future has been secured.
or you could do what i did: rob a bank, make the wife pay the mortgage, and the kids pay their own college tuition if the brats even get in!!!