How well do Tillandsia species like streptophylla, ionantha, grow if night temperature are in the 70's in the summer? Are there any species which cannot grow in those conditions? Thanks!
The species you've listed will grow very well with temps like that. Usually plants coming from high altitudes: 2500m + take exception. They prefer cooler nighttimes. These species are not readily available but sometimes species such as macdougalii, oaxacana, and matudae can be found but they are a very difficult grow.