"sherlock" wrote in message

I also would be more concerned about the Redtailed black shark than the
Kribs. The Krib's have a large enough tank and the Ram's will learn to
keep
their distance. How big is the Redtailed shark?,if it's small then it
will almost
certainly get more aggressive,if it's large and is not aggressive then
you might have the only one that isn't.

OK, thanks to everyone who replied. Seems I have no need to worry.

The redtail shark is about 5 inches. He's a nice fellow. After meals he
chases the barbs for a while, but has never done any harm. And anyway, the
barbs tease him, so its not surprising he responds. I am aware that he may
become a problem as he grows, but so far all is well.