Decapsulated doen't take good as Newly Hatched, so the fry don't take it if you don't train them
I feed the fry Newly Hatched at day 5, then after 2 week I train them to eat Decapsulated ... Put Decaps in warm water for 5 mins, then feed together with newly hatched. They don't take at first time, but if you train them well they will get it by increase amount decaps and decrease amount newly hatched each time you feed ... until you replaced newly hatched with decaps ...
Good luck!