Help with purple SPS

[J-Dog]

So my tank has been running for a few months now and I can't seem to figure out why my purple SPS keep fading in color. All my parameters are steady (alk 9, cal 400, mag 1250, nitrates 0, phos 0), so I don't really know where to start. When I first put my frags into my new system, everything looked great......then eventually lots of frags started losing color. A couple months later, most started coloring back up again, except for the purples. I wanted to test my system again recently by adding another bonsai frag.....and over the next week or two, it continually got lighter in color. Does anyone know what I can do to fix this issue? Please help, thanks

 

[3Twinklets]

It may help you to read the article that Feh shared about color.

 

[Downbeach]

What are you using to measure your parameters with? Especially PO4.

 

[.Marshall]

I'd say up feeding to get some more nutrients and bring mag up a little bit, 1250 is on the low side.

 

[J-Dog]

It may help you to read the article that Feh shared about color.

I have no idea who Feh is.

What are you using to measure your parameters with? Especially PO4.

I have a Red Sea test kit for most things and a Hanna checker for phosphates.

I'd say up feeding to get some more nutrients and bring mag up a little bit, 1250 is on the low side.

I tried that already....increased feeding and turned off the skimmer, but no improvement. I can try raising my mag.......but having it at 1250, wouldn't that affect all my colors, not just purple?

 

[Downbeach]

I have a purple nana that I use as a barometer to know when my PO4 is creeping back up, and I know it's time to change my GFO. Other than that it's sensitive to how much light its getting. So, how are your lights? What are you using? When was the last time you replaced the tubes/lamps? Water clarity could come into play here too.

 

[J-Dog]

I have a purple nana that I use as a barometer to know when my PO4 is creeping back up, and I know it's time to change my GFO. Other than that it's sensitive to how much light its getting. So, how are your lights? What are you using? When was the last time you replaced the tubes/lamps? Water clarity could come into play here too.

I have a 185 gallon tank (60x30x24) and I am using a 10x54w ATI Powermodule. The tank has only been running for 4 months, so I know the lighting is not an issue (bulbs don't need to be replaced). Someone else told me to stop using my carbon reactor, since that might causing the problem, but that hasn't worked either.