For SOD, you can use the method of (Babior, Kipnes et al. 1973).
For LP, you can use the method of (Uchiyama and Mihara 1978) .For CAT you can use the method of (Jiang, Xu et al. 1998) .
I used all of these methods in the 96-well plates on zebrafish homogenates and they will give you a very reliable results. Sorry for the late reply, I just saw the question.
Let me know if you have further questions since we both work on Z.fish and oxidative stress.