Thanks for the detailed information.
After changing the weather algorithm to OWM this morning, I have logged the Water Level changes during the day:
8 am: 19 %, 9 am: 31 %, 10 am: 48 %, 11 am: 52 %, 12 (noon): 53 %, 2 pm: 61 %, 3 pm: 69 %, 5 pm: 72 %, 7 pm: 68 %, 8 pm: 57 %, 9 pm: 53 %, 10 pm: 45 %, 11 pm: 1 %.
These changes look very strange to me. It was a sunny day with temperatures between 14 and 26 C, no rain today. According to Zimmerman temperature, humidity and part of the precipitation of the previous day shall be used for the calculation. Is this the case? I don’t understand the changes?