Leachate - The liquid run off (or seepage) that settles in or below the vermicompost or worm castings. Check for accumulated leachate in your vermicomposter frequently (when you feed, or weekly).
Worm tea – The end result of suspending worm castings in highly oxygenated water (brewing).
Below is a link of recipe of worm castings tea. There are many other recipes over Internet. But this recipe only use sugar as food source. Other did use liquid fish fertilizer and seaweed / kelp liquid fertiliser as well. Some said it is recommended to place the bucket under the sun to absort heat while the water aerated.