Coralline or Other Algae

[BigHildy53]

My tank has only been running about 4 weeks. It has live sand and live rock. The live rock was cured outside of the tank for about two months. I don't have fish or inverts in it yet. I started noticing what I hoped was coralline algae; little bits here and there. However, in the past about three days it has spread rapidly; which makes me concerned that this is brown algae. Under bright lights it may have a slight pink tint to it. Under blue it's light brown. I've attached a picture taken underwater with a GoPro.

Tank: 180g plus Trigger Systems Emerald 39 sump.
Alk: 8.4
PH: 7.8
Amonia: 0 ppm
Nitrite: 0.017 ppm
Nitrates: 2.6 ppm
Phosphate: 0 ppm

Lights are on from 10:00am to 11:00pm.

 

[reeferfoxx]

If it's pink under white light, then most likely coralline.

 

[kashman100]

Try to brush or blow it of the rocks. If it comes off its not coraline. Coraline will be green and other colors in the early stages and then change to pink

 

[BigHildy53]

It is brown Algae. Other than brushing it off and water changes, any other solutions?

 

[Diesel]

Yes........... let your tank cycle through!
Your tank isn't there yet and seeing this is normal.
All part of the process.
If no livestock or anything in the tank why do you have your lights on for 13hrs?
Turn lights off for three days and it's gone.
How did you start up your cycling process?