Sorry, I don't mean to simplify stuff (but I can't help it) ???
I was trying to say, that having observed a similar sympton, I was able to correct it with very little difficulty. In my case it was lack of oxygen that created the problem but treated soon enough it was fixed, no meds, nuffink... just a tad more air.
Thru this site and others I have relied on just a couple of rules, water, more water, and a constant environment. I was only offering a hope, that if, like I, negligence had played a part, a water change and more air might help. Did for me....twice!!! Jeez, I hated saying I did twice !!! :-[ :-[ :-[
(Name withheld for reasons of looking like a twit)