what is wrong with his tail?? pic heavy

i thought charlie had over flared and torn his tail but i went out on friday and when i got back saturday there was another tail and it over all just looked ragged. he hasn't lost any length and theres no abnormal black. (he does have 1 or 2 spots of black on his tail but they are always there) like i said he hasn't lost any length but it appears theres less red and more clear than before. the pictures didn't do a good job of catching the ragged but i took over 100 pictures spread out through friday, saturday and today. on the 16th i did about a 95% water change and completely re arranged his tank, maybe should i not have done that? also on friday i added live bamboo. but i noticed thursday night hes at the back of the tank and just swims back and forth a long the back of the tank, not leaving the back of the tank often which is unlike him, he usually used the whole tank. i tried taping paper to the back and sides of the tank but that seemed to bother him more so i took it off on saturday. so how do i fix this?

Housing
What size is your tank? 45 gal long
What temperature is your tank? probably about 75 because my room is around 80 always
Does your tank have a filter?no
Does your tank have an air stone or other type of aeration?no
Is your tank heated?no but my room is always very warm
What tank mates does your betta fish live with? none

Food
What type of food do you feed your betta fish? some kind of tetra idk they are micro pellets and "enhance color"
How often do you feed your betta fish? twice a day

Maintenance
How often do you perform a water change? once a week but i use a turkey baster to suck poop out a couple times a week
What percentage of the water do you change when you perform a water change? usually between 80-95%
What type of additives do you add to the water when you perform a water change? none

Water Parameters:
Have you tested your water? If so, what are the following parameters? no

Ammonia:
Nitrite:
Nitrate:
pH:
Hardness:
Alkalinity:

Symptoms and Treatment
How has your betta fish's appearance changed? tail is splitting
How has your betta fish's behavior changed? staying at the back of the tank more than normal
When did you start noticing the symptoms? 6/19
Have you started treating your fish? If so, how? no
Does your fish have any history of being ill? no
How old is your fish (approximately)? bought may 12 2014