I had a few poison potions 'disappear' from my inventory a few times during game play. At lower levels it isn't much of an issue... easier to replace at lower levels. But when I had "Huge" and "Giant" sized potions go 'poof', I knew had to find a solution.
Turns out when I was making poison grenades, or flasks, etc., it would use my poison potions when it had the icon for an ooze barrel (which is what I thought was being used) in the combine slot. (i.e. Ooze barrel + empty flask) So in other words, even with an ooze barrel in my inventory or on the ground next to me, and having chosen it as the source of the poison (I right clicked the barrel, then chose the other item) to make the items, it still ended up using my poison potions instead! (i.e. poison potion + empty flask) So I removed all my poison potions and placed them in a nearby empty container, then proceeded to try again. This time it worked exactly as it should have, it made a poison flask by using the ooze barrel and empty flask. Picked up my potions from the container and placed them back on my hot bar/inventory, and everything was back to normal. Problem solved. =)
Hope this helps a few people down the road.
Peace Out!
