Help diagnosing algae on coral

[Cashda]

I've already turned off the light for three days and covered the sides with towels but it continues to grow and take over the coral...please help

 

[Dkuhlmann]

Can't make it out in those pictures at all. Need to take the pictures with the actinics off.

 

[billdogg]

The blackish patch looks like cyanobacteria to me - just carefully siphon it off - even daily if needed until it finally goes away. Increasing the flow in the area will help.

 

[heathlindner25]

The blackish patch looks like cyanobacteria to me - just carefully siphon it off - even daily if needed until it finally goes away. Increasing the flow in the area will help.

+1 looks like cyano, its a bacteria not algae.

 

[Cashda]

Thanks for the help