Hello, and thank you for sharing such a wealth of information with all of us.
We have a Betta that we bought at the pet store ~1 year ago. He lived in a 5 gallon tank until recently when we upgraded to a 26 gallon aquarium. Several months ago, Jax got fin rot, which we originally treated with Maracyn 2. It improved, but he never regained the full length and size of his fins, and has continued to struggle with fin rot ever since.
About 3 months ago we got a more accurate water test kit and realized that we have quite the fluctuating pH situation going on. It will start out around 6.8-7.0, then within a few days it drops to 6.2-6.4. We have tried all kinds of things like pH Up, pH 7.0 (in moderation - we know that trying to correct the pH with too many chemicals can harm the fish.) We've added several coral rocks, and still the pH drops alarmingly. (Wondering if the acidic pH is burning his fins or if it is truly fin rot? He is red, and the edges of his fins have never looked black or white as some descriptions of fin rot say, but it sounds like fin rot based on the shrinking and shredding of his fins).
The fin rot recently (1 month ago - shortly after moving to the 26 gallon tank) got much worse - his tail is shredded and split, we tried a few rounds of Maracyn again, and Bettafix (which I then read not to use - so confusing - everyone has different advice). We were advised by a pet store employee to try an antifungal and an antibacterial, so we just completed a 10-day treatment of API Pimafix and API Melafix. It does not seem to have helped at all.
We are at somewhat of a loss as to what to do, it feels like we have tried everything and we love this little fish and don't want him to suffer. Thank you for any tips and/or advice.
I'm enclosing before and after pictures for a comparison. (the lights in the tanks and in the room are different, so it makes his color appear very different)
What size is your tank? 26 Gallons
What temperature is your tank? 79-80
Does your tank have a filter? Yes
Does your tank have an air stone or other type of aeration? Air stone
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 (Aqueon Beta Food)
How often do you feed your betta fish? Daily (4-6 pellets)
How often do you perform a water change? Weekly
What percentage of the water do you change when you perform a water change? 25%
What type of additives do you add to the water when you perform a water change? Stress coat, Aquarium salt, Top Fin Bacteria supplement, AmQuel Plus Ammonia Detoxifier, pH 7.0
Have you tested your water? If so, what are the following parameters?
Ammonia: 0 (though we had a recent spike after the antibacterial and antifungal treatments, so just did a full water change and it is back to 0)
Symptoms and Treatment
How has your betta fish's appearance changed? His color is a bit less vibrant, fins are shredded and shortened
How has your betta fish's behavior changed? He's less active but still an eager eater!
When did you start noticing the symptoms? Originally ~6 months ago, it has been off and on since then.
Have you started treating your fish? If so, how? Have treated several times with various treatments, none of which seem to help permanently (Maracyn 2, Bettafix, Pimafix, Melafix - see above for history).
Does your fish have any history of being ill? Only with the fin rot
How old is your fish (approximately)? 1 year?