Hot tubs are great to have until they require maintenance. One of the most common maintenance chores is cleaning the filter and there is no easy way of doing it. Sludge has a way of getting deep into the filter making it difficult to remove. Thankfully, the kitchen dishwasher can make the chore a bit quicker and does a thorough job of getting the sludge out.
Scrub between the filter divisions with the toothbrush under very hot water. The easiest way to accomplish this is to do all the ones on one side. Then flip the filter and scrub the other side. This is the only way to loosen the sludge between the filter divisions.
Place the hot tub filter in the top rack of the dishwasher, adding 1 tbsp. of baking soda to the detergent dispenser. Put the control on the hottest setting and press start.
Run the dishwasher for 4 minutes. Open the door and gently move the filter a few degrees left. Let it run 4 more minutes and move the filter again a few degrees to the left. Repeat until you have totally rotated the filter one full turn.
Flip the filter around on the dishwasher rack and repeat the 4 minute intervals. Then let the dishwasher complete the cycle, rinsing away the sludge and baking soda.
Replace the filter in the hot tub receptacle.
You may repeat this process as many times as needed throughout the season.