big zoos

[cla337]

I have a small group of the midnite zoos..you know the purple ones with the orange skirt. They were small and the colors contrasted well at first, but slowly they've multiplied,but also they got much larger (a bit less than dime sized) and the color is pretty "brown"...the purple and the orange arent very bright. What usually causes this...too much nutrients? too little light? Not enough flow?