36g in 9 hour while your away at work? You go to work and come right home from work every day of your life for the rest of your life? Never go away for the weekend? Or leave for a sporting event right after work? Never too busy to look at your tank one evening. Roll the dice long enough there is a chance we’ll see a disaster thread related to this topic.
Small reservoir can only put so much in a system. I’ve dumped 5g of fresh water into my system before with out any issues. I have a 5g reservoir for now. Later on I may switch to 10g after I’ve thoroughly tested the system enough that I trust it and upgraded to a slightly larger sump.