Green Terror Whirling, Erratic swimming

[Maxcredits]

I have a Green Terror that began 'chasing its tail' about 4 months ago. I see no signs of disease. Her appetite is fine. She is in a 65-gallon tank alone and the water parameters are all perfect. Temp is about 79 degrees. I have some videos that show the behavior although she is a little calmer than usual when she is being recorded

When this developed she was on a steady diet of frozen bloodworms because that is all she would eat. Before that, she ate pellets happily and has since gone back to pellets. I sometimes give her some freeze-dried bloodworms.

I do 30% water changes weekly. For about a year and a half before this started, she would lay eggs every couple of months or so. Of course, with no male, they would die off.

When this first started, she would be normal for awhile and then start the spinning. When she gets into the aggravated state her color darkens significantly. I would say that whatever it is is progressing because she is spinning almost all of the time or laying on the bottom in a corner. Sometimes the whirling gets violent.

I've tried several things but I'm running out of ideas. Any suggestions would be great.

Here are a few videos:





And here is one when she eats:



Any ideas would be greatly appreciated.

Holy mackerel - I just noticed this a saltwater aquarium forum. Sorry about that folks. I guess the name should have clued me in.

 

[nautical_nathaniel]

We can help with freshwater too!

What is your ammonia like in the tank? Have you ever treated this fish for internal parasites or bacterial infections?

It may also be distressed from being the only fish in the tank, you may want to add some dither fish.