Freeze dried food can cause constipation and not very nutritious. I used freezed dired bloodworms and FD brine shrimp but I changed them to frozen ones. It's so much more better, nutritious and my betta doesn't have constipation since. If I were you I would use the frozen foods.
Oh, I was just wondering. I give my bettas frozen food and Hikari betta balls. So, it does give them some sort of constipation? Does flake food do it too?