Hello! Recently I purchased a veiltail betta fish from chain pet store. He was admittedly not kept in the best conditions, having sick bettas in the compartments next to him, however he looked healthy enough so I bought him. Not long after him I noticed his fins were clamped up and he wasn't swimming much (I assume because it is difficult for him to swim with his fins clamped). I've examined him as much as possible and he seems fine other than the clamped fins. He's happy to eat and I feel as though he wants to swim but its difficult due to his fins so he just rests a lot. I thought it may be because of the filter stressing him out but that's been off for a few hours now and there's no change. I've been told that fin clamping is a symptom of something more serious but I can't work out what it is and I'm worried he'll suddenly deteriorate and I won't be able to do anything. I should mention that this is my second betta. I had one in this tank about 2 months prior who died for reasons I'm not entirely sure about. However I've replaced the gravel and ornaments and washed the tank thoroughly with hot water.
What size is your tank? 20 litres (about 5g)
What temperature is your tank? 26.5 degrees celcius (about 80 degrees farenheit)
Does your tank have a filter? Yes (currently off)
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
What type of food do you feed your betta fish? Hikari Betta Bio-Gold
How often do you feed your betta fish? Two pellets twice a day
How often do you perform a water change? I was going to do 25% weekly but because he looked sick I did 25% yesterday and 25% today.
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? Water ager/dechlorinator, KH buffer, aquarium salt
Have you tested your water? If so, what are the following parameters? N/A don't have a testing kit
Symptoms and Treatment
How has your betta fish's appearance changed? His fins are clamped, he also looks a little bloated but he may have been like that when I bought him, I didn't really notice.
How has your betta fish's behavior changed? He doesn't swim around much, just rests at the bottom.
When did you start noticing the symptoms? About 2 days ago
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)? I've only had him for about 4 days