TestLive Revision (398570/34354)
Currently you are only allowed one active potion buff at a time. If I drink an Elixir of Vigor first and then a Tears of Gullah, I get +60 HP first and then that buff is overwritten with +12% Follower Damage. We went from being able to stack every potion effect (in Live) to only one at a time (in 3.0) and there is nothing in the patch notes (that I saw), which is a fairly large stealth nerf.
Special fish also got moved from a potion buff to a food buff (which makes sense) but food also only allows one active buff at a time. Sadly the Aspect of the Wolf helm is currently acting as a food buff so it overwrites any other food buffs, see my bug report for details:
In short, is the potion system working as intended or is it bugged?
If this is intended, please reconsider allowing us to have multiple active potion buffs, the same as it is in the current Live version. Only one food buff at a time seems fair, as long as you fix any armor effects that are currently acting as food.