You need Springtails for them when they are that young. You could reach out to Josh's frogs via phone and see if they can overnight you a couple Springtail cultures. You could even try www.neherpaculture.com. They have springtail breeding kits. I would get 2 cultures and 2 breeding kits. You will want to make sure you have plenty on hand to feed them till they are big enough to eat fruit flies. It will take the springtails roughly a month to have the first "Boom" in the population so keep an eye on how many you have till then so you don't deplete them. Set both cultures up to breed and then feed off of one of them while letting the 2nd go forth and multiply

You will also want to get some fruit fly cultures. Start with the D. Mal type. Get 1 culture of it and some supplies to setup more cultures. Those kits can be found on either Josh's Frogs or NeHerps site. Start culturing them them now so you can practice and make sure you can do it consistently before your frogs are ready to feed off of them.

Your location says Henderson. Where is that? You might be close enough where I could give you some spring to tide you over till your shipment arrives.