BETTA BREEDING(will this work)????????

ok so i have one pair of bettas that will breed but the male alwas eats the fry and non of my other bettas will breed so i thot o would breed that 1 pair that will and only have 6 inches of water and then wen the fry hatch take him out rite away then lower the woter to abut 6 inches-my q is will this work?????????????PLEAS!!! I RILLY NEED TO KNOW:(!!!!!