Tail biting turned to fin rot?

[Seki]

My DT male has been biting his tail after the most recent water change. I noticed this evening that the ragged edges of his fin have a red look to them, and now I am worried he is developing fin rot. This has happened literally in just a few days of him biting his tail. I am in the process of trying to cycle his tank, so I don't want to take him out, nor do I want to disrupt the cycle by putting a bunch of medications in there, but of course I will do anything I need to do to help Zen.

Housing
What size is your tank? 5.5 gallons
What temperature is your tank? 80 degrees
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? Aqueon pellets
How often do you feed your betta fish? 3-4 pellets 1x a day, fast Saturdays

Maintenance
How often do you perform a water change? 2x a week
What percentage of the water do you change when you perform a water change? 50%
What type of additives do you add to the water when you perform a water change? Was TopFin water conditioner, switching to Prime this next water change (scheduled for Monday, but I may bump it up to tomorrow)

Water Parameters:
Have you tested your water? If so, what are the following parameters? Not tested, though I have the liquid ammonia test kit and strips for everything else.

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

Symptoms and Treatment
How has your betta fish's appearance changed? Upper lobe of tail fin is raggedy. The edges are a bloody red color.
How has your betta fish's behavior changed? It hasn't
When did you start noticing the symptoms? Tail biting, no more than 2 days ago. Redness just this evening. It wasn't there this morning.
Have you started treating your fish? If so, how? I haven't.
Does your fish have any history of being ill? Not at all.
How old is your fish (approximately)? Not sure. I got him a couple weeks ago at Petsmart.

[aokashi]

Do more frequent 50% water changes. every second day or every day.
Adding Aq salt will help and wont disrupt your cycle either
the dosage is 1tsp/gallon you can up that to a maximum of 3tsp/gallon for severer cases. watch your fish for negative reactions to this.

[Seki]

Thanks, aokashi. I will do a water change first thing tomorrow morning, then. I have read using Aq. salt isn't safe past ten days... if I am only doing 50% water changes, will I ever get it all the way out of my tank? I don't want to damage Zen's labyrinth organ by keeping him in constant salt... :(

[aokashi]

it will be fine :) just do a 100% at the end of 10 days ^____^ it shouldn't affect your cycle. if you are worried, you can run your filter in a container of old tank water whilst you change it out.

[Tikibirds]

You can put him in a storage container to do the salt treatment, if you don't want to put it into the cycling tank. Just make sure to cover it with something in cause he is a jumper.

The bacteria you want will be mostly in the filter cartridge and some on the substrate, walls and decor. There isn't much in the water itself.

[Seki]

Thanks, guys! I will put the salt in as soon as I have the opportunity to run to the pet store and get some. For now, I'm going to do water changes every other day and see if that helps at all. I should be able to run to the pet store Tuesday.

I have an old 1/2 gallon bowl that was sold to me when I got my first fish (don't worry, he was in there for less than a week before I found this site and got him into a 2.5 gallon). Would it be better to put Zen in there for salt treatments?

[Seki]

I need help, please. Zen's fins have gotten significantly worse, even with the daily 50% water changes. He has now shredded the bottom lobe of his tailfin, too. He is still swimming easily, eating normally, all that, but... the tips of his fins look awful, and I'm really seeing red on some of them. I never see him biting his fins... could there be something else going on? I know he could be doing it when I'm not around, but... it seems strange, because he didn't do it for two weeks, and then suddenly he shredded his tailfin. I've checked all of his decor... nothing sharp at all, and he has silk plants. Could it be the filter? Sometimes I see him sleeping sort of near it, but not right next to it...

I can run to the petstore today to get AQ. salt (I haven't had a chance to get it yet... store's over half an hour away and I work), and I plan on it. Should I put Zen in a QT tank for salt treatments? Like I said above, I have a 1/2 gallon I could put him in for treatment. Would salt baths be better for him, maybe? Please give me some advice, his fins are getting a lot worse... :(

[MoonShadow]

Would it be possible for you to post a picture of him? My thoughts are that his tail biting has led to an infection in the fins. Either a bacterial infection leading to rot, or an infection of the blood better known as septicemia. A picture would really help me help you further!

[Seki]

I have a few pictures. He wouldn't stop moving, so they are all a bit blurry. You can't see the red that well...

[MoonShadow]

To me that looks like he's biting. I have a tail biter and I never see him bite yet his chunks of his fins mysteriously disappear. No one really knows why bettas tail bite, it could be stress, boredom, he might be trying to make his fins lighter to cart around, or it could be other things! The red could possibly be infection caused by the tail biting, clean warm water and aquarium salt should do the trick!