Thanks for all your replies! I just wanted to give you an update!
She seems to be doing well today! Yesterday she ate and then laid down again but today she is up and about and seems back to her usual self. I did try the garlic drops, which may have helped. She also had a unusualy large poo. (LOL sorry if TMI) so I wonder if maybe she was having tummy troubles. Poor Fishy!
I've been giving her fresh peas and freeze-dried shrimp instead of her usual pellets and veggie wafer discs just in case it was a digestive issue. I'm keeping my fingers crossed hopefully she has no more issues.
Ps. I tested ammonia, there was none present, but of course I had done about a 75% waterchange since she started laying down. I tend to doubt it would be that though since the tank has been set up since 2006 and the nitrites were 0 and nitrates were only a 10.
I appreciate all the advice! Nice to meet you all, Glad I joined this site!
