Little help please

[Murice]

Tips have lost some of the neon color and turning brown... can anyone tell me what causes this?
1.024
40 nitrates
460 calc
14 dkh
8.2 ph
Tank about 3 months old, thanks for your help

 

[TripleTruble]

Where’s it sitting compared to light intensity and flow? Also dkh seems a bit high

 

[TripleTruble]

Also how long have you had it?

 

[Murice]

Also how long have you had it?

Had it about a month... sits about 12" from light, moderate flow... guessing par is around 100