I think the brown spots are normal- just a bit of "pineapple-ing". He definatly has fin rot (his tail in the third picture). Like callistra said, use aquarium salt. I would not do it in his normal tank because of the tank mates, they may be sensitive. I'm kind of shocked your mom won't let you do water changes. Honestly though, it's a life at risk vs making your mom mad. I bred bettas without my parents knowing once lol.
I feel so stressed out and useless- I can't do anything until Wednesday, all of the stores are closed. All I can do is set up his QT tank and even that feels like I'm hardly doing anything! I feel so bad for Pigg, he's my first Betta and I do really love him. Do you have any suggestions on what kinds of medications I can use on him and how I can prevent this from happening again or to my other fish?
It's ok! The fin rot isn't extreme yet, so it's ok until Wednesday if you do what you can. I would stick with aquarium salt, which you can buy at a pet store. The best prevention for fr is clean water.
Clean water does wonders for fin rot. Don't stress. Just get him in the clean water and he'll be ok until you can get meds or salt.
I like Seachem Kanaplex but it can be hard to find. You can buy it online and just keep it on hand.. if your mom will let you. Otherwise I like Maracyn Plus as it's a good broad spectrum. Furan 2 also is good for most things. All of these should treat that fin rot easily.
finrot happens with water that isn't cleaned often enough. Sometimes bettas can bite their fins or get snagged on things (like your filter) and that leaves them even more sensitive to the possibility of fin rot, but with really clean water fin rot doesn't happen.
And I would be VERY cautious with a tank that was sanitized with soap. I would rinse it out like 20 times again and then re-sanitize it with boiling water.
Okay. Breathing deeply, my head has cleared. I just need to type this down for a third time so it sticks- pick up friend's aquarium, set up the QT tank, drive to every pet store in a 30 mile radius to ask for Aquarium Salt, do frequent water changes and add the salt appropriately. Do I add the water from my main aquarium to the QT or just fresh water or a mix of both? Tomorrow is also cleaning day for my main tank so I can have the water at the ready and just leave the gravel vaccuming for a couple of hours.
I missed the soap.. I don't know if I'd use that.. but if you do it needs to be rinsed like you think you're losing your mind.. glass should be okay if you rinse it well enough. Plastics can hold onto residue more. In the future, aquarium equipment can be cleaned by soaking 10-15 minutes in a 10% bleach solution or pure distilled white vinegar. Anything porous (like ornaments, plastic, ceramics, etc) should not be bleached because they can hold the bleach and release it over time back into the tank.
Okay, I'll write that one down- I'll also inform her for the future. That may have been what got my Mollies when I was nine... I always cleaned their tank with soap :/ After they died I didn't get any new Mollies until I was twelve and I never knew it was THAT bad. I have never used it on any of Pigg's tanks, though. Oi... So much to learn! Thank you so much Callistra and Matt- you guys may just have save my boy's life!