My RCS have turned dark. Why?

I was about to say "what iis 'dark'?"

Many times RCS will darken up as they age, particularly the females. I've had a few that I would have described as burgundy rather than cherry, though they were a nice cherry when they were younger. No rhyme or reason, water quality stayed the same with the same feeding schedule and water parameters. They just darkened as they aged.

As long as the population is remaining steady (and for cherries that means increasing) and you aren't seeing females drop eggs, or having a noticable die off, I wouldn't worry too much.
 
The color change that you really need to worry about is if your shrimp turn milky white. That's a sign of severe stress and imminent death.
 
These have turned kinda purple but dark. The PH is about 8 which is the same as in my 55 which has bright red cherries. These guys are in a the cheese ball container tank which gets a 75% water change every 2-3 days. It is well planted with a sand bottom and has driftwood and rocks from established tanks. I use no filtration and see nothing out of the norm for behavior with these guys and they have been spawning. The tank is lit with an LED desk lamp and the plants are growing.
 
Yes. I feed these guys shrimp pellets and the others get tetra min.
 
TRay adding some spirulina pellets in their diet. Inverts need both meaty fppds and veggie foods. just like us! ;)
 
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