Betta with chunk missing out of tail?

[slade428]

My half-moon Erebus has had a strange thing happening to his tail in the past few days. I was waiting to see if I could figure out if it's fin rot, but I'm not sure it is. At first, it just appeared as though his tail had become shredded at the top, with a small chunk missing. Now, though, there's a large chunk out of his tail, and no more shredding. All the rest of his fins look fine. I've attached a photo... Any ideas? Is he getting caught on something, or is it fin rot?

 

[Derekkaine]

What do you feed him? Is it possible he is just hungry or maybe it got caught on something and part of his tail broke off.

 

[shellieca]

What size is his tank? Have you tested your water lately? What is your water change routine? Have there been any changes to his environment lately? Do you have any plastic plants? What about your filter intake, could it have been sucked into it? It's possible he's nipping his own fin, I've not had this experience with my own but I have read about others seeing their Bettas do this. Sorry for all the questions just trying to narrow down what it might be. If it were fin rot you'd see black edges

 

[slade428]

What size is his tank? Have you tested your water lately? What is your water change routine? Have there been any changes to his environment lately? Do you have any plastic plants? What about your filter intake, could it have been sucked into it? It's possible he's nipping his own fin, I've not had this experience with my own but I have read about others seeing their Bettas do this. Sorry for all the questions just trying to narrow down what it might be. If it were fin rot you'd see black edges

He's in a 5 gallon tank. Parameters are all good, I usually do a 30-40% water changeout once a week. No changes in his environment, and all the plants are real. The filter is on one of the lower settings, because I found the current was causing a lot of drag with his fins.

I don't notice any significant discoloration around the edges, and it's not looking any worse... I guess I'll just wait and watch.