As of right now I have just a tiny 6 US Gallon tank and would like to get a second tank. I found a used one for sale that is a 55US Gallon tank, glass, no scratches or cracks and was wondering if this would be a good size? The owner told me it was standard dimensions so I'm assuming 48"x13"x20" or something close to that. He'll sell it to me for $100 including decorations, rocks, heater and basically everything he had in it. So is this a good fit for price and my level of expertise or lack of... Also considering that i'm just starting our pretty much, with this size of a tank, what would be the ideal setup, fresh water or salt water? And yes I understand that a salt water tank takes more work. Thanks