Re: R. imitator froglets
Neonate and transitional care of amphibians is a special interest of mine.
The provision of shallow water to froglets seems to be another outside the box thing, which I find somewhat confounding. I think the fear of drowning is overestimated and easily preventable.
Your streamlined, efficient modality with tilted cups is valuable.
I have always provided a shallow pool and plenty of air exchange with good success.
Air and Water.