Do discus change color throughout the day?
I recently got my first two discus. I did about 6 months of research and preparation before getting them and they seem to be doing okay but I noticed something strange and I can't seem to find an exact answer for what I am seeing online... my discus seem to rapidly change color throughout the day and one (red marlboro) gets almost white at night when I turn the lights out while the other (turquoise striped snakeskin) turns almost black. Throughout the day the red one will gain and lose color, going from red with blue fins to yellow/orange with black fins and the turqoise's stripes seem to fade and darken all the time.. is this normal.. I keep obsessively checking the water parameters and temperature but they have remained stable and perfect according books (soft, ph 6.5, everything else looking good, temp 84).