Hi! I recently got a PPP cutting that was previously in water. So, when I brought it home I put it into our propagation station (rubbermaid container with holes in lid and two air stones) and under a grow light. The roots have continued to "pop" but I'm worried that it will rot before it has a substantial root system and also worried about the transition into the potting medium. I am currently rooting a Albo monstera directly in the medium (orchid bark & perlite) next to a humidifier. Has anyone had success rooting a PPP using this method?

PPP is no different than any other philodendron. Just treat it as you would any other you have rooted. Its not special because its PPP (and was likely super expensive). These used to cost $20 15 years ago. Their prices are super inflated now, and people tend to somehow conflate EXPENSIVE with HARD TO PROPAGATE. But its not that way. Its not expensive BECAUSE its hard to propagate. Its expensive because people are greedy.

So just treat it like any other hilo you have grown

Thank you for the response!!! I really appreciate it!! So with these little roots it's ok to go straight to my aroid mix?

Personally I would have skipped water altogether and used Sphagnum. Or, if there were sufficient roots, just gone straight into mix

I bought it from a local seller, when I picked it up she gave it to me in a cup of water. I didn't want to shock it too much so I just popped it in to our propagation setup. I will remove from the water. Do you suggest moving into moss with the roots it has or taking it directly from the water and put it into my potting medium?

I usually put stuff like this in moss if it only has a couple small roots. You do know that philodendrons and many many Anthuriums and other aroids can live indefinitely in Sphagnum moss, right? I have a few species that have never seen anything but moss.