Hi am am a newbie researching tubs. iterested in hot springs aria but can buy a grandee for nearly the same money. I felt that the aria at 365 gallons would be much less costly to maintain,chemicals, electricity etc,compared to 500 gallon grandee. however dealer stated that there would not be a noticeable difference as more water volume dissapates contaminants quicker, and easier , and overall the grandee would be much better value. Any input will be appreciated. thank you.