Dendrobium help

[wildstripe]

I recently got a dendrobium orchid (my second orchid, the first being a phal, which is doing nicely). I just have a few questions about it. It was doing fine, when about two days ago the leaves towards the bottom lost their rigidity, and are a little droopy. Also, the growth on the stem is a yellow-ish green colour, and I don't know if that's supposed to happen? D;

The flowers are also starting to all die (I can't tell if they're all seeming like that because it's not getting enough of something, or if they've just been in bloom for a long time).

I took quite a bit of pictures, and after I had to nurse my phal back to health (when I got it the roots were completely black and mooshy, and it was just a mess...it wasn't exactly the best thing for a beginner, but I learned a lot).

You can see white dust on the leaves (which is something from the store I got it from? It doesn't wipe off and I don't know what it is), the yellow growth-ish areas. And one last question because I know I'm asking you all a lot, should I not keep my orchid indoors all the time if it's really cold air conditioning? I don't know the humidity, but I live in Florida so I think it'd be better if I put it outside where it can breath more?

[WhiteRabbit]

Glad you found us!

I don't see anything that looks concerning to me. Others may spot something I am missing, tho.

The 'dust' looks like mineral deposits perhaps - foliage splashed (especially if there's fertilizer in the water) - if that's the case, it should come off with a bit of lemon (or other citrus) juice - just lightly moisten a bit of paper towel with the juice and wipe it. Tho it probably isn't hurting the plant.

The plant may just be shedding old foliage - can you post a pic of the whole plant?