How about Danio's or White Cloud Mountain Minnows? Or perhaps some types of gourami (their breeding is rather similar to betta's/siamese fighting fish) or corys?
Kribs are supposed to guard their young from other hungry fish... Hopefully I will see first hand in a day or two. I just had a female lay her second batch of eggs.
It's fun to watch the kribs chase away the cories, ottos, and tetras...