ok, I sprayed the dente with fungicide (Captan) at full strength, I recorded the date on the callendar, and next week, I'll repeat the treatment again.
I'm hoping even if I don't save the adult plant on the dente, the babies in the pot will survive, as they still look fine.
I'll have to find something for the akai ryu to immerse it in. Should both plants have the same treatments as the other one since they were next to eachother? Or should I wait to see if they develope eachother's symptoms?