Tiger Barbs-Lighting

[Sandzee23]

Hi, I got a new light today which i'm really happy about because now I can actually see my fish. Anyway this light is like nothing these fish have ever experienced in a long, long time. My weak old light is what they are used to and, for the last month no light at all. When I turned on my light I saw an automatic change from my tiger barbs mostly the larger one. He found shade straight away and starting breathing heavily, his black stripes started turning grey and i got a bit worried. I turned off my light and he swam out again and started being his normal self, when I swiched the lights back on he had regained his black stripes but hid again. I've left the light off alltogether now and I want advice. Can anyone tell me why and how to deal with the problem?

 

[Mr Spoon]

I had this problem with my tiger barbs when i upgraded the lighting. I added quite abit of wood, tall plants and floating plants, this made my fish feel more secure and they started swimming around again. How many tiger barbs do you have? they seem happiest in groups of 8 +