Broken spike

[Strange Design]

Hello!

I have never posted here before but I thought I would give it a go! We have a few Phalaenopsis (I think that's what they all are). We don't know a lot about them. I had a questions about one of them and was hoping I could get some help.

So one of my orchids met my preschooler and it didn't go so well for the orchid. The spike broke way at the bottom. The spike had 2 leaves at the time. We stuck the spike in some rooting hormone and stuck it in a plastic bag with some cotton balls and water. It actually seems to be growing good! It's been about 2-3 months and it now has 3 leaves and a new root is shooting out opposite the leaves!

My question is how long should I leave him in the plastic bag of water? I looked at the end that is in the bag and nothing seems to be happening down there. I thought about changing the water because there was a little blackish tint starting in the water. And if I do need to change the water should I add rooting hormone again?

I really can't believe this guy is still alive! I just don't know what to do for him next