I have 3 groups (n=5 per group) from biological data. I have checked the normality of my groups using the Shapiro-Wilk test and two of my groups are normally distributed. However, the 3rd group values are all zero. Should I use a parametric test (ANOVA) or a non-parametric test (Kruskal-Wallis) test to compare the 3 groups?

Other groups with similar data have done an ANOVA but I am not 100% sure why they consider the group with all zeros to be normally distributed.

Many thanks for your input!