Hello, I'm hoping someone on here might have some input into a mysterious disease I've been experiencing over the past two years.

I'm a terrarium hobbyist and have collected and grown countless rare/uncommon gesneriad species over the years. Starting about two years ago I began noticing a strange blight that now affects much of my gesneriad collection. It usually starts with the lowest leaves, the tips start to get brown and crispy. Over time all the lower leaves go brown and crispy and it slowly works its way up to the younger leaves. I'm experiencing this with plants that I'd previously grown easily for years in a variety of conditions (terrariums, grow bins, large glass cabinets). Even most propagations will eventually show signs of it, which makes me worry that it's some sort of systemic virus/infection. I've noticed this on nearly all my gesneriads with Diastema, Kohleria and Pearcea being the worst affected, and Nautilocalyx and Columnea being moderately affected. I grow roughly 100 species of terrarium plants and from what I've seen the only others plants affected by this are Pilea.

Really hoping someone can give me an idea of what is going on here. It's been driving me crazy as I've had to chuck out so many nice gesneriad species that I used to grow with zero issue

Hi！Just saw your post, @EcoTope
Could you please upload a photo? You can use the "choose file" button at the bottom, or copy/paste it.
Perhaps it may have something to do with the soil? Perhaps your soil mix is not sustainable for long periods of time and might compact or something else might be happening.

11:30am : Dale Martens program about the Impatiens Necrotic Spot Virus

Join Zoom Meeting Link:
https://us02web.zoom.us/j/8649...

The Nat' Capital Area Chapter of the Gesneriad Society have a guest speaker
this Saturday, Jan 14th at 11:30EST you are welcome to attend. Violet Barn
has been infecting the collections of many growers, mainly on the east coast I think.
You may want to watch although your symptoms were not the same as far as I know.
Personally I am investigating nectar...I have so much on my S. leucotricha
Donna Beverin

Ah, NSV.
Hope your sinningia is fine; it's very cute.