Unless the adf catches the neon off guard getting close enough, he won't eat it. Frogs aren't very fast and would have to get close to the neon to be able to snag it. I have 5 adfs with cherry shrimp and though they have tried, they've never caught a shrimp that I have seen. The shrimp are way too quick. Plus the frogs can't lunge if just free swimming. They push off on something when they lunge. The tetra would have to be either swimming near the bottom or next to something the frog can hang onto. As for the betta, idk. I've read both good and bad on that pairing. If you get a frog, get at least two. They are more active when they have companions.
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