For me, I usually tweak the "HP ALERT" bar based on following: The pots I'm using to autopot What kind of damage does the monster deal (touch or magic) Example, char has 5000HP. 1) Monster deals 2800 damage. Pot is Elixir (50% HP+MP heal), I set it roughly at 50% as I can't tank 2 hits with 5000HP. 2) Monster deals 1000 damage. Pot is Elixir. I set it roughly 25% as I can tank ~4 hits with 5000HP. 3) In a paranoid scenario. Pot is Elixer. I set it above 75% for autopot and also assign a HP pot like Melting Cheese (4000HP) to a keyboard key in case autopot fails (manual pot). You have to play around and see which suits your play style best.
