Tank (75gal) has been up for around 5 months now. All Marco Rocks except for one that I brought from my old tank that was 1.5 years old (upgraded after moving). Was wondering what algae this was? Is it really just diatoms still? I have a handful of Astreas and Ceriths that seem to be eating it but just want to know for certain what it could be. Have Chaeto in the fuge and a skimmer running as well.
Salifert Tests:
Nitrates: ~7ppm
Phosphates: ~0.05

Salifert Tests:
Nitrates: ~7ppm
Phosphates: ~0.05

