The color on the RTBS will fluctuate throughout the day. Within the same day I've noticed his color change from washed out to dark to washed out again. I'm sorry for not posting WP before, I plum forgot. Anyway here are my perameters GH is 0 KH is 0, NO2 is 0.5 NO3 is 0, and PH is 6.8. The light on the tank is a Marineland LED. It may be a bit bright but it's never on all day, and the blue LED's are on at night. I'm not sure what they should be stressed out about honestly, I put in four drops of love for every gallon in the water change lol. The thing that really get's me is that 5 of my 6 barbs are kinda washed out but the dominant male has never been brighter. That led me to believe it was something to do with a pecking order, but that wouldn't explain the shark.