"DGalt... separate your betta into the largest clean container you have handy to give him a rest. Put in some frilly live or plastic plants that he can hide in and a small air stone so he doesn't have to go up and down to breathe. Then after a few hours when he's settled into the new environment, just float one cube of frozen bloodworms in the water. Bettas can't resist those tasty worms... it's heaven compared to the freeze-dried ones (which have got to taste more like sawdust to them than actual meat)."
i agree with the solitary confinement, but make sure you are using current tank water when you are setting up the bowl, since a huge change in water could stress him more. i don't think an airstone is necessary, since the betta's labyrinth lung is specifically developed for breathing surface air, not for "catching" bubbles in the water. if your room temperature is warm enough you won't need to worry about a heater, but maybe put the container beside the other tank so he can still see the other fish. segregated bettas are lonely bettas, i know this much. depending on how big the bowl is, you will be doing much more frequent water changes, btw. seems mine are never ending.......
i wouldn't give a whole cube of bloodworms. what i do when its suppertime in my tanks is defrost a cube in a little tupperware container beforehand and use a toothpick to put the worms in the water. there is no way a betta could eat a whole cube in one feeding and not explode! lol. just kidding, but that is a lot of food that would end up rotting in the tank, which would make the fish even more sick.
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