Just a small update as I don't have much right now.
I found a paper with instructions for salt measurements for intense treatment from when I took my last betta to the vet. So currently Petrova is in a 3 gallon hospital tank but with only a gallon of water and he has aquarium salt, methylene blue (recommended amount for long term hospitalizations), and I have tannins depositing but I don't have much that will deposit however I ordered more almond leafs and a thermometer that will be here at 8am tomorrow morning (I forgot my last one broke :') ). He's also got a heater and a clean sponge filter in the tank because I am out of air stones too but the tank needs to be oxygenated since methylene blue eats up oxygen and I don't want him to have to fight for anything.
As for his behavior he's pretty still- he's sitting on a leaf at the surface which is exactly what I want him to do. He has swam a bit and seems to be handling that well though I can tell the loss of his fin makes turning a bit more difficult
My hope is that he recovers. I have had absolutely no issues with classic betta genetics like I have with many Bettas before and he's only ever had a small fungal infection which he healed from quickly. He's a resilient little guy. But I'm hoping the lack of issues I have had this far will mean he recovers
Best case scenario is the hole where his fin was fills up and the fin dies and falls off so there isn't large risk of infection. If I need to get him to a vet I can and will find a way but for now it's going to be a sit and watch game because moving him around too much will stress him more and I absolutely refuse to do that to him.
Hopefully he pulls through the night and I can get a better grasp of how we'll be looking tomorrow and how recovery may go.
For now this is how he's looking and I hope he recovers