Struggling with Tillandsia Brachycaulos — would appreciate advice

I want to be honest: I'm not getting great results with Tillandsia Brachycaulos and I'm not entirely sure why. scale insects or mealybug in the leaf bases has been a recurring problem despite my attempts to address it. I've been focusing on soaking in water for 20 to 30 minutes once or twice a week based on everything I've read.

extraordinary architectural forms from spiralling to globe-shaped is there in glimpses, which tells me the plant has potential in my conditions. I have it in a glass globe or terrarium with open ventilation which might not be ideal. most vigorous growth in warm humid summer months showed some improvement. Two stars for now — not the plant's fault, but not a success yet. I'll update if things improve.