We've decided to change the boys food from selective eating to just the one type. I know not to change it over right away because when we ran out of food last year and got a different one Sooty ended up ill. Tonight I've done it do it is 9 spoons worth of old food then 1 of new so that tomorrow it will be 8 of old and 2 of new. But I'm not really sure if it is the best way to do it because don't want either of them ending up ill. Is that way ok or is there a better way?