capricornis browning

[mrsmav]

i have a monti cap frag that just recently started browning on one edge. it looks as if is brown stained algae growth. the rest of the frag appears healthy. any ideas whats wrong??

water paramaters
sg 1.025
ph 8.2
ca 450
alk 3.0
ammo 0
nitrite 0
nitrate 5
phosphate 0

thanks

 

[mr pink floyd]

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