FirstGrow

Have you been placing the bottle in the background over the top of the seedling? If so, it could be a combination of suffocation and being too humid. Your plants need good air circulation to be able to breathe/transpire and have wastes removed via their leaves. Your other plant is four times larger and will have very different water requirements as compared to the little one. Leave the little plant uncovered, water it with a gentle hand, think moist, not wet and do not give it any fertilizer until she has recovered and is putting on growth again. Hope this helps.... Organoman.