Another dumb question- Red Slime or Coraline Algae

[rk4435]

I am in the process of installing my new sump. As I pulled out live rock I noticed what could be red slime, or coraline algae.

I have been having a cyano problem and my phosphates and nitrates have been high, which is why I took the plunge on a larger sump to allow for reactors etc.

The live rock in question has been in my sump for months with no light source or refugium.

 

[mcphock]

Does it come off easy? If so, it is not coralline algae.

 

[picoreefguy]

+1 coraline is a calcium based algae so you would have to scrape at it with your fingernail or something hard to get it off but if you can get it off by simply blowing water at it its probably red slime or diatoms.

 

[rk4435]

Thanks guys you were right. It was coraline. You're mind can go a lot of different places when you start switching a sump out late at night.