Sam12345

My hot tub is arriving in a few weeks. After previously assuming my patio was level, I have now discovered it has a 17mm slope across the width of the tub (2.2m). the supplier recommended a minimum of 5-10mm slope and has therefore suggested putting a base in to ensure their warranty isn’t invalidated. Seems a lot of trouble to go through for a minor slope but I’ve never owned a hot tub before. Any recommendations? Would it be very noticeable on the water level? many thanks! sam