I am having the exact problem with my fish which I keep in my classroom. His name is Steve Prefontaine and the poor guy is suffering. I did what was suggested by taking him out of the tank and placed him in a smaller container with fresh water. Should I completely empty the main tank and refill it? What is the next step? please advise
What size is your tank?
What temperature is your tank?
Does your tank have a filter?
Does your tank have an air stone or other type of aeration?
Is your tank heated?
What tank mates does your betta fish live with?
What type of food do you feed your betta fish?
How often do you feed your betta fish?
How often do you perform a water change?
What percentage of the water do you change when you perform a water change?
What type of additives do you add to the water when you perform a water change?
Have you tested your water? If so, what are the following parameters?
Symptoms and Treatment
How has your betta fish's appearance changed?
How has your betta fish's behavior changed?
When did you start noticing the symptoms?
Have you started treating your fish? If so, how?
Does your fish have any history of being ill?
How old is your fish (approximately)?
answer all of that to the best of your capabilities so we can best help you :)
You'll want to lower the temps to around 78-80 degrees. In a two gallon, you need to be doing two 50% and one 100% water changes a week. You need to be feeding him 2 pellets twice daily as well. I suggest buying a thermometer. You can get a little glass one in the fish/pet section of Walmart for one dollar.
It sounds like what Saix has been going through, ammonia burn. Get a liquid ammonia test and test your water. Make sure to change your tank water at least every other day, and put water conditioner in it. Don't forget to test it before you put him in.
He definitely has fin rot. Can you pick up some API Stress Coat or API Aquarium Salt at the petstore soon? If the fin rot reaches his body, he will be very, very, very, very ill. I know you're getting a lot of advice kind of piecemeal but the basics that everyone will agree on are
1) He needs a heater to keep his water at approximately 75-80 degrees Farenheit
2) He needs a filter or 100% water changes at least once a week
3) He needs water conditioner like API Stress Coat or Seachem Prime
4) Two aquarium thermometers
5) An ammonia test kit. Later on, you will need test kits for nitrate as well. When you can afford it, you will probably want to get a master test kit that tests nitrate, nitrite, chlorine etc. For now, you definitely need either a liquid drop ammonia test kit or ammonia test strips.
Once you are able to obtain these things, you will want to do the following
1) Change his water. Make sure the water you put back into his tank is the same temperature as the water he was in and also make sure you condition the water. This is why you need two thermometers, one to measure the tank water and one to measure the water in the bucket you will be putting in. Stir the water vigorously to remove as many gas bubbles as you can.
2) Because he has a bacterial infection, you will want to do partial water changes once a day because you want to get the infection out of the water. Be sure to add Stress Coat or Prime every day when you do these changes. It's very important that he is able to build up his slime coat again.
3) Feed him good quality food, only a few pellets at a time. They need to be small pellets because bettas have small mouths, so food made especially for a betta are a good idea. Try and remove uneaten food.
4) Test the water every day to make sure there are no ammonia buildups. It's doubtful there will be if you are changing it frequently but it never hurts to be sure. Later, when he's healthy and you are no longer changing the water every day, you will want to test for ammonia every day.
5) Just watch him. If the redness in his tail gets closer to his body, post again and let everyone know. You may need to get tetracycline then.
I know it sounds like a lot of work but if you can get the little guy to pull through, you will be rewarded with a happy little fish with lots of personality.