Hello.
I have a newish betta named Ollie who lives in a planted 10g tank by himself. A few days ago, I noticed that his black gills were extended out from under his gill flap. However, he isn't showing any signs of breathing heavy (no gasping) and he is fairly active. He's also had a small lump in his abdomen since I purchased him, and it possibly looks a little bloated now. I am not sure. Do you think this could be gill flukes? Gill hyperplasia? I have never kept a betta before.
After doing some research, I immediately did a quick strip test to make sure water parameters were right, and nothing seemed wrong. Low nitrates, no nitrites, and less than .25 ammonia. I can do another test tonight if it will help with the diagnosis. A water change is due soon. I prefer to do 40% every few weeks as that method has been working for me and keeping things stable.
I keep his tank around 77 F, but can easily raise the temperature if that will help. I used to keep it at 80F, but turned it down. I can't remember why. I feed Ollie a variety of betta pellets, floating and sinking, and give him just a few pellets every other day (approximately). Tonight he seemed to be stressed by the flow of the filter so I turned it off temporarily. His filter is an internal filter, and the flow is pretty low, but I am considering getting a sponge filter instead to make things even better.
I would appreciate any help. I have mardel maracyn, ich-x, and Fritz ParaCleanse on hand. I can easily get aquarium salt if needed.