Here are four photos of the issue. The first two are a mini Catt and the second two are a standard Cattlianthe. Both in semi-hydroponic-culture. Both receive the same care. Water with rainwater. Using K-lite @~100ppm weekly, Quantum Total weekly, and Kelpak monthly. There is a white substance which has formed on some of the surfaces above the substrate.
The mini has two new growths approx 2 months old that have yet to put out new roots.
Temp range 65-85°f. Humidity 55-70%. There are small fans in the grow tent that move air lightly.
Anyone have an idea what I'm looking at?