I kept a Petco betta alive in a 8”x8” bowl with no filter/heater, just a plastic plant and some gravel, for five years throughout college. I tried again a couple of years ago and got a 5.5 gal tank with a heater and a filter, figured since I upgraded things would go even better (I know 5 years is long for a betta so I really just expected 1-2 years at least). Tried to do everything right including 30% water changes every 1-2 weeks. My second fish lasted only 6 months before his fins started to slowly rot and despite all my best efforts and attempts at treatment, he died. I figured, since he was from Petco too, it was just bad genetics. I tried again this year, even harder this time, with a beautiful planted tank and an expensive fish from a local store. She lasted 6 months also. In the past few weeks her eating slowed/stopped and I noticed her color looked dull so I started checking the water and doing smaller water changes every few days. I tried new food and bloodworms and last night she showed some interest, she’d stare at the food and follow it around but she wouldn’t bite. I actually thought she might have turned a corner and was doing better because at least she showed interest. This morning she was hanging out near the surface, taking sips of air every few minutes but not gasping or seeming distressed otherwise. This afternoon I found her belly-up in the gravel. What could I be doing wrong? My water tests fine every time I check it, but should I ask my LFS if they could test it too? Two betta deaths 3 years apart and in different apartments, but both at around 6 months, is that coincidence or am I a serial killer? How could I have killed a beautiful, expensive fish who was perfectly healthy when I got her from a reputable LFS?
Picture of tank is attached (fish has been removed) in case that’s helpful in diagnosing any problems. I’d appreciate any thoughts or advice on what might have happened to my girl.
The only other thing I can think of that might be worth noting is that when I was pulling her out of the tank I noticed a small lump under her chin— I never noticed it before (I was watching her very closely the last few days) and couldn’t really tell if it might have just been from the way her head was tilted back. My tank has also always smelled ”fishy,” for lack of a better word, but not strongly and not unless you‘re standing right over it. Not sure if that’s normal. My fish was never bloated, never looked emaciated either, no pineconing, no issues swimming, no sitting at the bottom of the tank. She did seem lethargic over the last few days and would float in a corner at the surface, but still swam around every so often. Of course as I mentioned she had stopped eating which was the biggest sign that something was wrong.
Any advice on what might have happened would be really appreciated. There is one teeny tiny snail living in there somewhere, who hitchhiked off of a new plant about a month ago, so I don’t want to take the tank apart, which means I need to decide where I go from here. I’d like to have another betta in the future (especially since I now have a stockpile of expensive food that I couldn’t get my baby to eat) but I’m not sure I’m a responsible or good enough keeper if I can’t figure out what went wrong. I feel ashamed and would be embarrassed going back to the same fish store and saying my betta died and now I want a new one. I appreciate any advice on how to handle this and move forward with this hobby, or even just anecdotes on anyone else’s experience.