1 scoop is half ounce. I'd say the scoop size is maybe 1/4 cup.
notice King's 1/2 oz is $2, vs Aqua lab of $5, and they never had it whenever I go there or call. just a waste of time.
at $2 a scoop, you do not need to breed/raise them. just buy more as needed. I just keep it in a container with holes on the cover (and clearly marked fish food) in the refrigerator, and replace the rodi water once a week, no feeding. most google search will tell you do replace the water every day, to feed it , etc, etc, which I think is all unnecessary.
also blackworms are freshwater worms and dies within 10-15 seconds in saltwater. as such it is not a natural food for any marine fish. and not all fish will be interested in it. so I think the piranha feeding frenzy is not quite accurate. in fact when I first dropped some blackworms into the tank, all fish freaked out and went into hiding. it's like I have a fishless tank for like 20 minutes. also, when you google how to raise/breed, you will find one that feeds the worms cardboard/newspaper. I don't see how these worms can be highly nutritious if all they eat is cardboard.