Please Help! My Betas Tail Is Turning Pink!

Hello, I'm new to this website, but I have a half moon beta, Sapphire, is dark blue at his head and it gets lighter shaded of blue going towards his tail, not too light, still solid blue then the tips of every fin is bright white, or WAS bright white!! his top fin is slowly turning pink a little bit every day, it is spreading! what can I do to help him? I love my little Sapphire! he's my little gem, lol. please help me find out what is wrong with him!
 
Sapphire lives in a 1 gallon tank, with sand bottom, 2 live plants, 3 sea shells, a little glow in the dark cave, and a junk filter that came with the tank, its just a little box with a charcoal filter in it with a detatchubal water pump at the bottom of it. I feed him BettaMin tropical medley.. oh I also got this little moss ball thingy in there with him... my mom got it for min at Pet Co.. I think that is everything there could be to know about his living environment. oh also I have previsley needed to fill his tank with tap water a copuple times because I could not get to the store for him. we have hard water here, ALOT of iron in the watter, we use a well... we use cloriean and other chemicals in it to treat it. but I used the water filter from the fridgeorator door to fill his tank.. it was purified, but to be safe I use these drops called BettaSafe water conditioner.... I think that is everything! I will put up a picture of him just as soon as I figure out how...

hi,
how long have you had him?,
rough guess on age?.
this might just be his mature colours
my crowntail is dark blue but has a green tinge in the light so its not uncommon to have lots of colours.

Butterfly bettas (ones with a coloring pattern like yours) are marbles. This means they change colors. Nothing wrong there.

The pics are not very clear but it may be normal pigmentation, he is very nice, my understanding of butterfly bettas is clear areas to the fins only were as marbles can change colours on their body as well as fins.

Yea the pics aren't that great but from what I can tell is that it looks like normal pigmentation. Bettas do change color especially when they're young (I'm no expert so idk when they stop changing). I do know that bettas like warm temperatures between 78-82 with 80 seeming to be the preferred on this site. So maybe that can help you out. Again without a better picture quality it's hard for us to tell what the deal is.

I agree with the other members.
If the fins had pink edges that look fluffy thats a sign of bacterial finrot.