Clamped fins on betta? How do I treat this?

[Kennanator]

Started noticing my betta in the past month or so developed symptoms of clamped fins. Other than that he's moving around and eating normally. How should I go about treating this?

Things I've done so far :

1. 40% water change, will start doing 25% water changes more frequently if needed
2. Purchased betta mirror so that he can flare and stretch his fins out for a couple of minutes per day or every couple of days

Following are my tank parameters which seem pretty normal and in good shape :

• Tank size:
  • 10 gallons
• Heater and filter? (yes/no):
  • yes
• Tank temperature:
  • 79-80°F
• Tank Parameters:
  • Used API Freshwater Master Test Kit ⁠
    • Ammonia: 0 ppm
    • ⁠Nitrite: 0 ppm ⁠
    • ⁠Nitrate: 2.5 ppm
• How long have you had the tank? How long have you had your fish?:
  • Had the tank and betta for 8 months
• How often are water changes? How much do you take out per change? What is your process?:
  • Approximately 25% water change every 2 weekS. Should be doing it more often to be honest. I use a gravel siphon every week and scrub the walls about once every 3-4 weeks
• Any tankmates? If so, please list with how many of each:
  • 7 Pygmy corys
  • 5 neon tetra
  • 2 nerite snails
  • 3 Amano shrimp
• What do you feed and how much:
  • Tetra BettaMin small pellets. I feed him once per day with 4-5 pellets
• Decorations and plants in the tank:
  • red root floaters, frogbit, Java moss, Java fern, annubias, dwarf sagittaria, spider wood, chola wood

[Colu]

Clamped fins can be caused by poor water quality disease  what your pH KH GH does he seems stressed by his tanks have you noticed any aggression any rapid breathing hanging out near the surface lethargy @Kennanator