please help purpleish/blue spots and new tests

[TeamReefWreck]

just noticed some purple and blue spots on the plastic parts on my filter, small about 10 or so. the tank is 4 months old 40 gallon salt water, reef, corals no fish just did a 80% water change sunday because of ich infestation and tested the waters on monday. any help would be great thanks, Kevin

alk 2.8
amm- 2.8
no3- 12.5
no2- 0.1
3/4- .25
ph- 7.8

 

[TylerHaworth]

I would say that the purple/blue'ish spots are Coralline Algae growing...

Those water parameters are WAY out of whack though, these numbers lead me to believe that your tank is cycling...

N03 is a little high
NH3 should be zero
N02 should be zero
pH should be higher in the 8.0-8.2 range

Fill us in a little more on your setup and history of the tank and maintenance practices so someone more wise than I can help out when they see this!

 

[BobBursek]

Could be coraline algae, Pic would help.