There are many factors that cause cloudy water.Here are som tips that may help clear the water.
First things first:
Do you know when the last time you drained your hot tub?
Your hot tub water must be drained every 3 to 4 months. Sometimes you'll need to be drained more often. One of the most important factor is your usage if you use your hot tub with 2 or more people, more than 3 times per week - you are a high usage soaker! 2 people X 3 times per week X 4 week a month is 24 people per month.
On average each person sweats 1 pint of sweat per hour - do the math; thats a lot of sweat!
So, it's best for water clarity to drain the spa at least every 3-4 months!