To be honest i have never heard of that food but all i would say on the matter for you is not to change the food because he seems bored with it as you will find yourself doing this every week, when he realises that you change it every time he goes off of it he will play you at that game on a regular basis and you may regret doing it. Find a good super premium food (meat based not cereal based) and stick with it if i were you. You could try soaking it and see if he prefers it wet.