Extremely Clamped, Hiding, Won't Eat At All, Please help!

[Aroe]

What size is your tank? 20g
What temperature is your tank? 80 degrees
Does your tank have a filter? Yes
Does your tank have an air stone or other type of aeration? no
Is your tank heated? Yes
What tank mates does your betta fish live with? 4 other female betta fish

Food
What type of food do you feed your betta fish? Aqueon Betta Pellets, Zoomed Betta Pellets, Sun dried shrimp, bloodworms once a week
How often do you feed your betta fish? 3-4 pelletsd each everyday with one fast day a week

Maintenance
How often do you perform a water change? Tank's been set up for a week.
What percentage of the water do you change when you perform a water change? 75%
What type of additives do you add to the water when you perform a water change? Stress coat, water conditioner, a little aquarium salt

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

Ammonia:
Nitrite:
Nitrate:
pH:
Hardness:
Alkalinity:

Symptoms and Treatment
How has your betta fish's appearance changed?
How has your betta fish's behavior changed? She's very clamped, hiding a lot, won't eat anything, color faded a bit
When did you start noticing the symptoms? 2 days ago
Have you started treating your fish? If so, how? No
Does your fish have any history of being ill? No
How old is your fish (approximately)? 1-3 months?


She's never been this clamped or hid this much and she's always been a good eater... nothing's changed in the tank either... She's also really fatigued... Please help Rizz!

[Aroe]

Anyone? I'm really worried about her, she's usually very active

[callistra]

Why are you adding aquarium salt?

Can you get photos? It's only this one betta?

I would qt and float in the main tank for warm in something she can more easily reach the surface in. In this I would do daily 100% changes for a while and see if she perks up.

[Aroe]

Initially, all the fish I got were very torn up so I added the salt for healing and stress purposes. What do you mean by qt?

[Aroe]

Yes. One betta's been clamping a bit more recently, but not all the time. The 3 others have no problems at all.

[callistra]

I mean remove her from the main tank. QT stands for quarantine.

[Aroe]

Okay. I'm changing the water today. She's still listless.

[callistra]

You can treat conservatively in the QT with 1 tsp per gallon aquarium salt predissolved.