Holy crap I was on my phone when I saw the pick of that chip and silicone job. I know you don't want to hear this cuz it sounds like a good deal and will be perfect for what you want to do with it but do Not buy that tank! That silicone job looks horrible. Wait you can find a way better tank.
Be afraid, be very afraid. That amount of water on the floor is more than you think when, yes when, it lets go.
Garage tank, at best. $200, for tank and stand, tops.
Thanks everyone for the feedback! I'm glad I posted this... I've already had a 72 bow leak. The last thing I want is 180 gallons of water messing up my house.