[LazyPup]

Most manufacturers recommend cleaning the piping system by filling the tub 1/3 to 1/2 full of pure HOT water and adding 1 to 2 cups of LOW SUDSING DISHWASHER DETERGENT SUCH such as cascade. (Absolutely do not use laundry soap or common dishwashing liquids as they are high sudsing and would flood the room with suds.)

Turn the pumps on and allow the soap solution to circulate for 30 minutes, then drain and repeat using HOT WATER only to rinse. (You may elect to add 1/2 cup of laundry bleach (Chlorox or equivalent) to sanitize during the rinse cycle.)

The air vent you mentioned is most likely the air intake for the areator function and it can be manually adjusted by the user to increase or decrease the ammount of areation.

In most instances these tubs do not require a filtering system because the water is drained and refilled for each use, however, there are some accessory filters available. If your tub has a filter you should contact the dealer to see how to remove or service it.

You should also not use Bubble baths or bath oils in these tubs as they leave a soap or oil residual on the internal pipe walls that encourages bacterial growth.