A month of no food and be fine??? I’m impressed lol it takes me 5 minutes before im wanting another mealAnd often necessary. I've had a few fish that I had to fast before they would eat artificial foods. I generally only have that problem with purely carnivorous fish. A FH should only take about a week tops before it should accept other foods. Either way tho they can go upto a month without food and just be fine, only really need to worry about it once it's past a month.