For the vial version, see Perfect juju farming potion.
[FAQ] • [doc]
Perfect juju farming flask detail

A perfect juju farming flask is a potion flask containing up to six doses of perfect juju farming potion. It is created by using a potion flask on perfect juju farming potion with at least six doses of it in your inventory. You can also talk to Teplin Macagan in Oo'glog to automatically fill up the flasks, even in noted form.

A dose of the potion is believed to last for one hour. While the potion is in effect, you have a 5% chance of getting harmony moss from any farming patch, and a 25% chance of getting two harmony moss at once from a harmony pillar, similar to the juju farming potion's effect on herbs.

After all six doses have been consumed, the flask will shatter and disappear. Only the original, six-dose potion is tradeable on the Grand Exchange. Once the potion has been partially drunk, no more doses can be added to it. However, if you wish to decant the flask into potions, you need at most four doses of potion left in the flask and an empty vial, decanting a flask into a vial will still make the flask shatter.