got a new male betta about 6 days ago. 3 gal tank with heater and filter. we had the tank up and running for a couple of days before we got him. checked all the levels are they are in the norm. he hasn't eaten anything we've put in his tank for him. we've tried all the foods we use for our other bettas and he just isn't impressed with it or something. we've tried pellets, dried blood worms and even went and tried flakes. his color is fine. his fins are in good shape. he doesn't have a bloated tummy. he isn't clamped up. I don't see any 'disease' on him. he isn't 'scratching' against anything like he has an internal 'disease' going on. he hovers around the top of the tank most of the time but is alert & 'flares' up when check him out. kinda at a loss of how to help him. tomorrow im taking everything out of the tank and doing 100% water change to see if that helps or not. anyone else have this problem before and want to share advice, itd be greatly appreciated.