Sick Betta?

[Ems993]

Hi all,
My name is Emily and I have had my bet ta Regina for about 3 months now. She has never really been very crazy, she usually swims around fine and hides a lot near the water filter in her tank. This past week she has been laying on the bottom of her tank, or on top of her princess castle. I don't really notice any discoloration on her that hasnt been there as long as I've known her. All she does now is lie somewhere. I have been doing 1/3 water changes every other day and yesterday I completely cleaned the tank and nothing seems to help. this morning I woke up and she was in the same spot she was when I went to sleep, and when I talked to her she swam around a lot and immediately sank back down to the bottom of the tank. It looked like it was hard for her to swim. I would greatly appreciate any help or advice from anyone.

 

[NickAu]

Can you please answer the following questions.

How big is the tank?
Has it got a heater? What is it set to?
Has it got a filter?
How strong is the current?
Is it cycled?
How often do you change water?
How much water do you change?
Do you vacuum the substrate?
What additives or chemicals do you use? Eg De Chlorinator?
Do you use tap or bottled water? If bottled water please give us the brand.
Do you have a water test kit?
Can you tell us the readings for ammonia, nitrite and nitrate?
When you clean the tank can you tell us exactly what you do.
What do you feed him? how much? how often?
Any tank mates? What sort how many?
How long have you had the Betta?
Has he got a history of illness?
Any plants or decorations? Please give details?
Can you provide a close up photo of the fish?
Can you provide a photo of the tank?