Furry fins? And white stuff on bottom of tank

Please help. I've had my fish for 2 days, and last night he was floating near the top (I assumed I had over fed him)...
This morning however, he appears to have a gross layer covering his fins (he is a crowntail).

Any suggestions?

Also, after doing a 50% water change yesterday, my tank has white powdery stuff on the bottom? What could this be? How should I get rid of it? Thanks

Housing
What size is your tank? 2.5 gal
What temperature is your tank? 26 degrees Celsius
Does your tank have a filter? yes
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

Food
What type of food do you feed your betta fish? betta bites (pellets)
How often do you feed your betta fish? twice a day, 2 pellets each feeding

Maintenance
How often do you perform a water change? changed his tank yesterday, 50%
What percentage of the water do you change when you perform a water change? will be 50%
What type of additives do you add to the water when you perform a water change? water conditioner

Water Parameters:
Have you tested your water? If so, what are the following parameters?

Ammonia:
Nitrite:
Nitrate:
pH: was 6.0 last time i checked
Hardness:
Alkalinity:

Symptoms and Treatment
How has your betta fish's appearance changed? appears to be a thin coating of white stuff on his fins
How has your betta fish's behavior changed? started floating near the top of tank
When did you start noticing the symptoms? last night - 12 hrs ago
Have you started treating your fish? If so, how? nothing
Does your fish have any history of being ill? not that i know of
How old is your fish (approximately)? not sure (only bought him 2 days ago)