I really know absolutely zilch about orchids but I think that repotting both of them in slightly larger pots and in moss would be the best thing to do.

I know that Orchids require humidity which these probably are not getting enough of because they are inside in air conditioning at around 70 degrees.

They get no direct sunlight just indirect through a window of which the sun never hits.
Although the one of which is doing poorly is sitting at a darker window.

I seem to remember something about using "Humidity trays" which the ones I saw were just a black plastic tray with a criscross plastic grid work to keep the plant from sitting IN the water and soaking any up.
I thought about just making one out of an old shallow pan and maybe buying some tumbled colored glass to pour into it.
Seems to me that would do the same thing and look a lot better. Or am I missing something?

But I have a feeling the ailment of this one plant is more than just lack of humidity.
What is the best way to repot an Orchid?
Size of pot, type of growing medium, anything special I need to do to the Orchid before or after repotting?
Any advice would be appreciated.
My 94 year old mother is just raving about these Orchids, she has never had any either and marvels at how long the blooms stay on them.
Which is another question, just how long do Orchid blooms last?

Anyway I was trying to ad 3 other pictures when I was so rudely interrupted by my own finger.

This is the base of the one that is doing fine which is the one I managed to post above.

This is the one NOT doing well.

and its base/pot

I water them about every 10-12 days, I soak them well, tilt the pot to drain out any excess and then in about 9-10 days I check to see if the pot is light and feels dry.
These were just watered yesterday
' '
. .

You have what is called a phalaenopsis orchid.
Phal blooms usually last anywhere from 1 to 6 months with 3 months being more the norm.
I think you're right-on with the one that is struggling, it does appear to need a repotting. If it were me, I'd repot it into moss also, just so you have them both in the same growing conditions. You can buy orchid moss at the big box stores. Pot it in a pot that @ the same size as the one it is in currently. If anything, keep it on the dry side for the first couple of weeks and then normal watering like you've been doing. If you want them to re-bloom, they'll need to get a little more light. Some direct light in the early morning or late afternoon helps, or some diffused light through the day.

Good luck,

Bob

So all the flowers dropping after about 3 months or so is the norm then?
and a small pot is actually preferred?

Shirley.
No the outer pot does not have holes, on one it has an inner pot that does not touch the sides or the bottom there is air all around.
The other is missing that inner pot and would definitely benefit from drilling holes in the pot or probably preferably just repotting in a new pot similar to the other one.

I will buy at least one pot for the one in the funky pot and improper medium and some Orchid moss.

Thanks again

The advice given is correct. Repot in new pots with good drainage or cut holes in the bottoms and sides of the existing pots. Use sphagnam moss or moss mixed with small wood chips. Water when 'almost' dry and increase the light. You can give some fertilizer each watering.

Both should recover and rebloom this winter. It would be helpful to know what zone the plants are growing.

Jane

Yeah I figured the one really needed a repotting I think the thin inner pot allowing air circulation all around the roots seems like a critical requirement for these plants.

I am in zone 7b

The one that is properly potted actually has a whole new branch and at least 5-6 more flowers about to bloom soon.
The other one has one flower left and no sign of any new growth, although the roots and leaves look to be in fine shape still.

Giving as much info on your growing environment, including zone and light exposure helps when asking for advice.

Jane