Your comment is the leaves are "erecting now" did that mean to say eroding?
If so likely needing more light.
Did the AR mini come from a fish store and was it in a bunch?
Did you plant it in a bunch or separate the stems by an inch or so when planting?
Need light to get all around.
Also may have been grown in a nursery like regular plants - not under water and having an issue in adapting to being completely under water.
How is the color, and if you are fertilizing and using some iron the color should be good. Making sure if there are fish uou do not increase CO2 too much at one time. And also increase the lighting gradually/ incrementally as well in which ever proportion you need to. Too much light increase at one time is not good for plants.