So i have decide to supplement the diet. I cooked an egg yolk and mashed it up very fine in water. I keep it refrigerated and will add a tiny bit each morning. it stays in the water column for a while so they have plenty opportunity to eat.
That is a common recommendation. For CPD fry the answer varies widely based on age. I am not a large-scale breeder, but had our 7 CPD become 28 in six months in a community tank. At the very earliest stages, the fry will graze on super super tiny food. The egg suggestion is usually for those fry. Apparently they are dark colored and lay in the substrate until their swim bladders develop some. Even then, they are so tiny you can barely see them. They still can't eat cyclops but will graze on other things in the planted aquarium. Once they are big enough that you can see them pretty easily, they will be able to eat cyclops. I suspect by what you are saying that these are not tiny fry, but are juveniles. Juveniles eat pretty much what the adults eat. I do not feed anything in particular to the <1 week old fry. I just keep enough moss that there are places to hide and little microorganisms to eat. I feed the rest of the CPDs crushed Tetra flake, live baby brine, and live vinegar eels. The vinegar eels are small enough that the younger fry can still take them, but not so small that the adults won't eat. The brine shrimp seem harder for the juveniles and fry, but are devoured by the adults and help with color. Crushed flake is my lazy alternative when I don't want to take the time for live food. I put a pinch between my fingers and slide them together to crush it into a fine powder. Hikari micro-pellets are too large and sink too fast, but sometimes I will crush them into powder as well.
Honestly, it seems like the most important thing to having them breed successfully and having fry survive in the community tank is to have plenty of moss or other fine plants for the fry to hide in and for the adults to lay eggs in.
I tried to add an edit but it wouldnt save:
EDIT: I watched your tank stream for a while, and was able to catch the fry. They are pretty small but are able to eat vinegar eels and crushed flake at that size.
Side note, do you mind sharing what camera and method you use for your stream? I am working on setting one up and would like something similar to what you did.