about a month ago, my fiance and i bought her mother a 2.5 gal tank and a BEAUTIFUL halfmoon betta for her birthday. we set everything up, made sure he had everything just the way he'd need it, and he died mysteriously two days later. we returned him to the LPS and got her a new betta from a different store (a GORGEOUS delta tail) and this one died a few days later as well. we've been all over that tank and there's nothing wrong with it, and the ADF we got her as a betta companion is doing just fine. my fiance's stepdad underwent some pretty intense radiation treatment a day before we got her the tank, and although he he made sure to keep his distance from it, i was wondering whether the radiation could have caused the fish to die. the only other problem we thought was that the food she had was the kind of pellets that fluff up in water so they float longer, and i was worried the fish might have been choking on the overinflated pellets. we really want to find her a new fish to go in there (Molly, the frog looks awfully lonely!) but need to figure out what killed the first two before we try again.
i don't have full parameters on the tank, but it's 2.5 gallons with aeration and an under gravel filter, and it's by her front door which is almost always open except for the glass pane door, so it's heated naturally. the pellets in question are TetraBetta Plus Floating Mini Pellets (http://www.petsmart.com/product/inde...lmdn=Fish+Food
) and my fiance's stepdad is no longer radioactive.