A tale of two dendrobium orchids

Hi All,
Back in 2021, when I started my orchid collection, I bought two of the same dendrobium hybrid. Both seedling plants, purchased at the same time. I treated them pretty much the same from the beginning. However, when I transitioned them to pumice, I tried potting them up differently to see how they would react.
Growing Details:
Perth Western Australia
Climate: Mediterranean
https://en.wikipedia.org/wiki/Climate...

Home grower
Ducted Heat and Air Con
Humidifier

Growing Media:

Pumice
https://www.aquaponicswa.com.au/categ...

Grow Lights
Full spectrum white light LED grow lights in either 10w strips or 80w bars

Water:
Under the sink R/O 5 stage filtration.