Ideally, you'd clean everything every time it's dirty. Sometimes, some of the tubs here get cleaned two or three times a day if we find them dirty over and over again (or tipped water bowl, etc). Keep the enclosure clean is one of the most important things you can do to make sure your animals stays healthy and stress free.

Wayyyy back in the day when I had snakes in tanks and used to use reptile carpet, I actually kept a bunch of extra pieces in a box under the tanks ... when a tank was dirty, I just swapped out the reptile carpet real quick and did a full cleaning when I had the time.

Sounds like you're on the right track with what you're doing ... but if you're snake is doing well and eating well, don't be afraid to do full cleanings more often than once a week if you have the time ... it will only help.

-adam