How do I maintain a wooden hot tub?

After you have drained the water, wash the hot tub with the clean water from time to time.
To clean from the inside you can use a brush or a pressure washer.
If the hot tub stands empty, do not cover it.
The air must circulate to prevent causing mold.
From outside it is necessary to treat the wooden bath barrel with wood oil or linseed oil at least once per year.