The water in the balance tank should be clear enough so the bottom is visible. You should see circulation coming up from the filtration return pipe.
Indicators the balance tank should be drained completely and cleaned:
- Visible items that can’t be cleaned out of the system
- XX the system can’t process
Otherwise, the balance tank will only be drained at the end of each season. It will be clean and sanitized before it is is filled up at the start of each season.