Have bot seen her eat here at my tank yet, but saw her eat at my friends tank before i brought her home.
Its harder to feed in a bigger tank i think? The food gets blown away instead of dropping on her. Hope she is able to eat soon
I personally would not have moved a ray this skinny. If it was eating at your neighbors house, I would have left it there until it had put on some weight. Sometimes after rays are moved, they go on hunger strikes even though your water may be perfect because they get stressed by a move. This seems to be on an individual basis but I wouldn't chance it with a ray like that.
However, what is done is done. My advice is to get live earthworms and use those. Stingrays are very sensitive to electrical signals put out by potential prey items, and this can be used to provoke a feeding response.
As soon as you get her eating, feed her a lot. She has been either riddled with parasites or denied a proper diet for quite some time to look like that. These things do not happen overnight. If you have already offered her 5 small meals a day, and she is back begging for more food, give it to her. Increase your water changes as well, and with good water and proper feedings, she should bounce back although it may take some time to undo this much damage, but is completely possible.
On a side note, it might be best to avoid whoever sold you this ray in this future.
Best of luck, and if you have any questions or need any further help, feel free to message me!!