Red Devil sick?

Looking for someone with expirience....
Background, I have a red devil that is approximately 9 yrs old. She was in a 55 gallon by herself until about a month ago. We moved her into her new 150 gallon home (still by herself). Tank has 2 fluval 404's and water is kept at 79. We did a fishless cycle on the 150, and when parameters were 0 ammonia, 0 NitrIte, and 20 NitrAte, we moved her in. Since we moved her, we haven't seen her eat, but food does seem to disappear in a day (sometimes)? She spends alot of time standing on her head staring at the bottom of the tank. No noticeable signs of any type of injury, fungus, or anything on her, and she dont have any problems swimming, fins are not clamped. The water paramaters are still good at 0,0,40. Her breeder tube is down. I guess my question is she seems mopy and just stares at the gravel at the bottom of the tank, is there anything I should be worried about or looking for?

I guess it is entirely possible. She has layed eggs in the past alot. But hasn't layed them in at least a year. I have heard of "egg bound", but dont know if it is a problem or is she just looking for a place to lay them?

She perked up a little the last couple days. Actually became aggressive, attacking the glass when we come near the tank. Another fish i dont think would be an option, i think she would tear it apart. There's times during cleaning that she attacks me. I am really more concerned about not eating. Haven't physically seen her eat since we moved her.

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Update she was fine after her episode and started eating again, but unfortunately she passed over nite. Hopefully it was quick...RIP my friend

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