[banjosnotbombs]

I would slowly introduce the Oxbow pellets. On the back of the pellet bag there's an instruction guide on how to switch over from your previous food to Oxbow in 3 weeks.
I believe it goes something like
1st week 1/4 Oxbow to 3/4 previous food
2nd week 1/2 Oxbow to 1/2 previous food
3rd week 3/4 Oxbow to 1/4 previous food
On the 4th week you're to feed only Oxbow.

I'm not sure how neccesary it is to follow this guide, but since it's reccomended that's the way I would go.