A hot tub's water level is extremely important for proper operation. Insufficient water levels can reduce heating, the water outflow from jets and water cleanliness from reduced filtration.
Look for the hot tub filter, normally located on the side of the tub. Fill the hot tub with water to about 2 to 3 inches above the top of the filter. Do not fill the hot tub above this level. As the jets are turned on and people get inside the hot tub, the water level will naturally rise.
Water Level and Filter Function
The filter sucks water into the internal plumbing of the hot tub and filters out debris. The water level inside the hot tub must be high enough so that the water flows inside the filter or the pump will not work properly.
Check the water level of a hot tub frequently. Natural evaporation or heavy use of the hot tub can quickly reduce the water level and reduce the effectiveness of the spa's plumbing system. Adjust the water level as needed so that the water is always about 2 to 3 inches above the bottom of the filter while not in use.
Watch for excessive water loss or pooling water around the hot tub, which may indicate a leak in the tub.