Betta girl breathing heavily?

[cjz96]

Just added my girls today to my cycled 55 gallon. One girl is still breathing heavily 12 hours later. Is this okay? Thanks!
Housing
What size is your tank? Cycled 55gallon
What temperature is your tank? 77-79F
Does your tank have a filter? Yes
Does your tank have an air stone or other type of aeration? No, but the filter does make some bubbles. It's a canister.
Is your tank heated? Yes.
What tank mates does your betta fish live with? 11 other female bettas, 6 panda cories, and 15 rummynose tetras.

Food
What type of food do you feed your betta fish? Homemade and occasional tubifex or bloodworms.
How often do you feed your betta fish? 5 times a week.

Maintenance
How often do you perform a water change? Once a week.
What percentage of the water do you change when you perform a water change? 25%
What type of additives do you add to the water when you perform a water change? Stress coat, prime, seachem flourish, seachem flourish excel.

Water Parameters:
Have you tested your water? If so, what are the following parameters?

Ammonia: 0ppm
Nitrite: 0ppm
Nitrate: 15ppm
pH: 7.4
Hardness: Will do test later
Alkalinity: Will do test later

Symptoms and Treatment
How has your betta fish's appearance changed? Breathing heavily.
How has your betta fish's behavior changed? Breathing heavily.
When did you start noticing the symptoms? Today
Have you started treating your fish? If so, how? No. Just been keeping a close eye on her.
Does your fish have any history of being ill? No, does swim oddly, always have.
How old is your fish (approximately)? 1 1/2 years aprox?

[callistra]

Your water maintenance techniques are very good and your water quality seems fine. It doesn't sound to be a problem with the water.

I would keep my eye on her carefully. If she's not better in a day or two or seems to be getting worse I'd QT her. How do you mean she swims funny? How long have you had her? What's her poop look like? Does she seem ok other than the heavy breathing?

Do you have a hospital tank you can keep warm if she doesn't perk up?