Okay, answering the questions first...
What size is your tank? 2 gallon
What temperature is your tank? 79 degrees
Does your tank have a filter? no
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? none
What type of food do you feed your betta fish? Pellets
How often do you feed your betta fish? 3 in the morning, two at night
How often do you perform a water change? daily
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? Conditioner
Have you tested your water? If so, what are the following parameters?
Symptoms and Treatment
How has your betta fish's appearance changed? lost over 50% of his tail, and some of his other fins
How has your betta fish's behavior changed? Stopped building bubble nests
When did you start noticing the symptoms? a few weeks back
Have you started treating your fish? If so, how? Aquarium salt and Malafix, as well as daily water changes
Does your fish have any history of being ill? No
How old is your fish (approximately)? 1-2 years
This all started a couple weeks ago when I noticed my five gallon tank was looking cloudy. It quickly clouded most of the tank in a nasty algae growth. Despite many water changes, and blackouts the algae has continued (and continues) to be a problem.
I noticed Biscotti's fins were shorter, and it seemed to be tail biting. I removed him from the algae filled tank and currently have him in a 2 gallon bowl. I've been treating him for the fin rot resulting from the tailbiting for just under a week. It isn't advancing, but the ends of his fins are a brown yellow and I'm concerned about continuing treatment with the Malafix and Aquarium salt. The fin rot isn't progressing, but it doesn't seem to be getting better either.