This show seems to be following the original "rules' on how kryptonite. There are (or were, DC/WB has changed everything but it's underwear ) that there are 5 kinds of kyrptonite.
Green- can kill Kyptonians.If exposed to a big enough piece for long enough.
Red - has all kinds of weird effects and no one piece can effect them twice.
White- kills all plants.
Blue- only hurts Bizarros. (imperfect duplicants of superman, etc.)
Gold- can take away their powers forever.
Big question: can kypronite hurt STREAKY? He's an Earth cat, but his powers are a duplicate of Kyptro's. My guess: MAYBE Blue kypronite could hurt him. Or take away powers temporarly?