I have a phalaenopsis with an aerial root that is approaching another pot. Is it possible to let this root go into medium and produce another plant (obviously not in with the catt) ? If not, what do I do with an unwieldy long root like this?
No you can't propogate the phal by putting your wayward root into a separate pot.
What to do with it? Basically nothing unless you are willing to repot the entire plant and put it in the media. I would turn the two pots to keep it out of the other pot.
I view Phals like little rebels with their roots. Always running away from home to go exploring. lol I just keep an eye on mine and make sure they're not in a position to be damaged or latch in/on to another pot.