Are my airplants slowly dying?

I got these at a farmer's market in the summer. The man who sold them to me told me to soak 'em every 5-7 days or until they looked gray/less green. He also mentioned to keep them under very strong light; I already use Barina lights for my other houseplants so I'm covered there.

I've noticed over time the leaves getting brown and crispy, but I'm scared of over-watering them. After I soak them I dry them upside down in their pots/cages under the grow lights. My office is pretty dry, so I assumed this would be enough to prevent rot.

The rightmost one has some loose bits on the bottom; if I touch them too much it feels like they'll fall off. The other ones feel somewhat fragile. Hopefully this is enough info for someone to tell me what I'm doing wrong/if I'm going crazy. (If you read all of this, thank you so much)