I am sure this is already well known regardless i didn't see it when searching the forum.
August Celestial quest where you ride a mount and put out the sha fires, you need to fill up your water cannon at the creek befor you begin to extinguish. As you know sometimes it takes two or three times to fill the cannon.
Instead of using 1 water cannon per flame, if you position yourself close enough to two of them, you can cast your first water canon, turn camera and cast towards a second without having to refill your cannon a 2nd time.
In essence, you can put out 6 flames with 3 canons instead of refilling for all 6.