mine are the same way. there was a similar thread a few days ago and someone said the ones whose stripes turn green are the males. totally normal though. mine with green stripes is healty and the dominant one in the group
Yes Perfectly normal.....3 of my tiger barbs have green stripes when there playing with each other. So ya perfectly normal all of mine are healthy and normal.
I noticed 2 of my females fighting the other day, and literally in front of me, I saw their stripes change from black to green, then black again in the space of 2 minutes!!! Very freaky, but I think it is just a mood change thing!!!!! Nothing to worry about!!