it seems with this hobby, you want to have around a hundred bucks extra then what you need to get started off in case something happens, equipment failure or having to repair something from water damage if your sump set up messes up if going w/ a larger tank.
a larger tank is great, im looking forward to upgrading mine, however, you want to make sure you buy a quality tank, you get what you pay for, and i think a few people dont realize that water weighs alot, a flimsy stand can leave alot of water on the floor, and if you happen to have a fish tank on the second story of a house, i cant imagine the amout of damage 20 or more gallons of water would do.
i would like to share with you guys a video of what could happen with a fish tank and please learn what to should the glass on your tank ever break... just yell for your mom.
YouTube - wow a kid tryin to lift weights breaks fish tank.
i would also like to add this video of a crab that looks like its dancing.