Self Contained Fresh Water Tank Accident

To me being able to see the tank level is the best of all possible solutions. My Dutch Star would siphon nearly 1/4 of the tank out the overflow after filling. I thought about cutting the overflow hose and putting in a valve to shut it off and decided the potential of me being dumb and forgetting to reopen it later after the tank level went down was too great.

Instead I removed the pegboard panel that allowed me to see the tank and determine when it was full, not relying on the overflow to tell me. Now I know what is in the tank and don't have to guess from the gauges which never seem very accurate.