The easy way to get this achievement is disable permadeath and no time to grind. Now play until you find a room with at least one fountain (better if you find the room with two fountain, its not so rare). Now take off the equip and find a moster or a trap close to the fountain room (alternatively you can find a way to disable your health regen) and damage you until you are 1-4hp. Now go close to the fountain and save the game. You can now try to drink from the fountain and if the effect its not acid reload the game and drink again, the RNG change the effect of the fountain each time you use it, its not seeded and you can abuse it until you get the acid and die.