I just bought a portable hot tub from Meijers and was wondering how long it takes to heat it up to 104 degrees. I have the filter and heat on to 104.The size of the heater is 1000 watts. The tub only cost 0 and holds 250 gallons. I have had the pump and heater running for at least 10 hrs. and the temperature is only 65 degrees. One person told me it could take about an hour a degree. Is that true? HELP!!