Feeding our Fish Worms

[Calico3]

Hello All : This may  be a very  usual question and will show my inexperience with feeding live foods. I do have 2 cultures of white worms and have raised BBS for my fry.

A email friend is now raising micro worms to feed her goldfish fry.  I do know that my white worms are not to be fed often because of the high fat content.

What is the difference between these two worms  as the culturing of them is different on line.  I hope to have additional fry this year and am very interested if it is a benefit for me to raise some.   Also are they available to purchase in the Ottawa area .

Thank you