Motes of Water can be a good source of World of Warcraft Gold. Farming for it will surely be worth your time. There are a couple of farming spots I could recommend for optimum farming experience. In my server, a single Mote of Water costs 2gold each and if you turn them into Primal Water they can bring you 20gold.
The best place to good for Mote of Water is Nagrand. You might be thinking that I might mention going to the Elemental Plateau but you’re wrong. The plateau might be a good place to farm but it’s always full of farmers that you might just be wasting your time there. There are pools in Central Nagrand that you can farm for Motes of Water without the need of a flying mount. The three mobs to look for are Muck Spawn, Lake Spirit, and Lake Surger. They have decent drop rate and you could collect a lot of Mote of Water in an hour.
If you don’t like going to Nagrand, there are 2 farming spots located in the Terokkar Forest just outside of Shattrath City. First off the list is the Sylmer Lake northeast of Shattrath City. This is where you can find Shimerscale Eels. You can easily get around 4 Primal Water in an hour of farming here. Best of all, its nearness to Shattrath City makes it convenient for you to empty your bags if they become full. They have an excellent drop rate although this spot tends to be overpopulated.
If you already have a flying mount, then go to the Skettis and kill Skettis Surgers. These mobs drop Mote of Water as well. A plus is that at level 70, Skettis Surgers are easy target. Last time I went to Skettis, I was the only one farming the spot.
You should take note that most Mote of Water farming spots listed here are underwater. Warlocks should have no trouble with their Unending Breath spell but other classes might want to use Elixir of Water Breathing or Nagrand Cherry so that you don’t have to go up for air and have a lot more time farming.
There is also another way of farming for Motes of Water. You can fish for them. Pure Water nodes could be fished 2 to 4 times with Motes of Water having a drop rate of 75-80%. Pure Water nodes could be found in Nagrand and requires fishing skill of 380 before you can do some fishing from them.