Yellowing leaf tips

[OrchidTraci]

I have noticed a few of my orchids are getting yellow leaf tips (I grow under HID lights). Could this happen from lowered humidity? I started to notice this when the temps dropped along with the humidity.

[LJA]

If it's just at the tips, that's usually a sign of toxicity buildup--fertilizer or other salts. Is it just lower / older leaves, or are the new ones being affected too? That'll happen a lot of times if you fertilize a plant that you've let go dry (it's always best to fertilize when the roots are already damp) or if you've mixed your fertilizer too strongly.

[OrchidTraci]

If it's just at the tips, that's usually a sign of toxicity buildup--fertilizer or other salts. Is it just lower / older leaves, or are the new ones being affected too? That'll happen a lot of times if you fertilize a plant that you've let go dry (it's always best to fertilize when the roots are already damp) or if you've mixed your fertilizer too strongly.

It could be a buildup. I hadn't fertilized in a while and could have shocked them. I guess it is time to flush them out.