My grey tree frogs were all eating within that time frame. I started with springtails and D. Mel fruit flies and started them with crickets about a week after that. All food should be no bigger than the space between their eyes. They probably will not bother with blood worms so I wouldn't even attempt it. Make sure they feel safe. Have some plants hanging in there for them to hide in and cover at least 3 sides of the tank. This was my baby greys favorite spot to hang out - https://smile.amazon.com/Zoo-Med-Lab...3&keywords=ivy