Becky,
I have been raising worms for just over a year now and have tried many different methods for separating the castings and eggs. I think that I have watched every youtube video on worm castings and there are so many different ways to go about this.
One thing to consider with this screen method is the size of your worms. It appeared in the video that he was using larger worms, which would be easier with a screen like he used. I tried this method and it was difficult for me. My worms are so small that they either went through the screen or got stuck in the holes and had to be painstakingly removed one by one. My screen may not have been small enough so I can't say for sure that I did it properly but I gave up on that method. Also, the castings were very moist and did not seem to flow easily through the holes. The eggs are so small that I think it would be difficult for a screen to catch them. Some people dry their worm castings first; but this seems to kill all of those beneficial microorganisms that we are trying to have.
I have seen several videos where food is placed on one side of the bin and the worms are removed as they cluster around it and placed in another bin, until they are all removed. At some point the remaining eggs will hatch and you will have new babies in the bin but this seems to be more thorough if you have the time. This method is not quick !! I do like this method the best so far and this is what I am doing.
Lots of people dump the entire bin or make small piles and wait for the worms to crawl down away from the light but this is really slow. I dumped my entire bin one day on a tarp and thought that I would never be done. I finally scooped them all back up as I didn't have hours and hours to give to the project. My 6 and 8 year old don't allow me the time needed for this method.
One thing that I do if I need some castings is to scrape them from the sides of the bin and place them in a small plastic shoe box container. I use a putty knife to sift through them and pluck out any worms and toss them back in the worm bin.
I can easily come up with a pound or two to use. The worms are not usually around the sides of my container so this goes pretty quick.
Since I have been mixing worm castings in my seed starting mix I have had great success with germination. I'm always experimenting and it's fun to see positive results. My worm population has more than tripled in a year and I am working on another worm bin as we speak. My wife doesn't appreciate them like I do !!
Hope my thoughts have helped.
