I've always been surprised so many people grow Tillandisas in terrariums. They have an enormous range, but nowhere do any grow in closed, highly humid areas. They are plants of air and sunshine.
The main difficulty in cultivation is that they are accustomed to heavy dew or rain most nights, and drying out in the sun the following day. The even environment in a house makes this difficult to replicate. They grow outdoors like weeds in areas with heavy nightly dew and daytime breezes. Constant mosture will rot them; insufficient moisture leads to them drying out. Some species have long, arid winters, when it is warm but there is no dew. So long as these dry out between watering they can be watered year-round. Others get dew almost every night.
As would be expected, the finer-leafed ones are more particular about adequate watering and not drying out. Tillandsia tectorum is in this group. Many people find it challenging to grow outside a cool coastal setting.
T. usneoides (Spanish moss) is more adapted to constant high humidity than most. I can understand growing that in a terrarium.
There is a group with large bulbous leaf bases and few white hairs, like T. bulbosa. They mostly come from very arid areas, and store some water in the bulbous bases. They do better in low-humidity environments so long as they are not overwatered. These rot easily in a cool, high-humidity or always-wet situation.
In large matter it comes down to finding plants that match your growing conditions.
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