Does anyone know what’s happened to my begonia? I got her 3 days ago and she was just fine. it isn’t sunburn as she’s sat in a dark room quarantining from my other plants before I introduce her to my collection She is in a self watering pot with regular water with a small bit of hydrogen peroxide in it (yes lower than 3%) because I have a small gnat problem and I don’t know if they’re in the soil I potted her in or not I removed the water yesterday and replaced it with regular water with nothing in it when I saw that this was happening to her. the big leaf pictured is the only leaf that has gotten worse in the last 15 hours