How to check betta fighter teeth recoil (Primary check)
See color fish if observe color pale that show defective.
See betta made bubble Nests. Perfect betta will made bubble nests everday. If don't made bubble nests or subnormal that show no good.
See vivacity of betta. Fish drowsily don't vivacity same normally
Fish eat very little or not eat
Good fighter will expand body ready to fight that show fish vivacity and ready fight. If fish don't expand and sleep below jar that show no good.