[garvis]

Great explanation/pics.
However I believe a 4 day old larva is too old.
I use 1-2 day because after the second day the diet changes.
Also you can buy cell cups if you dont want to go through the trouble of making your own.

 

[garvis]

He says 4 days old, but he means on the 4th day. That will be a 1 day old larva. He's counting the days it is an egg.