Green algae

reefaboo · Nov 3, 2014

what ever i do i am not able to get rid of this algae on the sand bed. this is mostly on the sand bed with an exception of 1 -2 inches on the rock work.

Picture is not mine but this is exactly what i have.

some ppl seems to think of it as green Cyano and i have read somewhere that its not actually green cyano but a form of green algae ( sea weed or lettuce algae)

here are my parameters

Sp. Gr - 1.026
Alk 8
Calc 420
Mag 1300-1400
nitrates - 0.5-0.75 (using red sea test kit)
Phosphates - 0.02 (using red sea test kit)

its def not flow related as there is abundant flow where this is forming.
i do feed a little too much but i have an over rated skimmer (rated for 180 gallons on a 50 cube) and run biopellets (even though its only about 1/12 of whats recommended)

please advise how to get rid of this stuff

thanks

Randy Holmes-Farley · Nov 3, 2014

Looks like a species of cyano bacteria.

Search on cyano to see what you find, but the general ways are reducing phosphate more than you have, increasing flow, manual removal, decreasing organics (more skimming, for example), lights out, and in last ditch mode, antibiotics.

reefaboo · Nov 3, 2014

How many Days of lights out is ok with sensitive corals and Nems ?

is only blue an option ? or does algae grow with only blue lights also ?

Reefing Madness · Nov 3, 2014

Thats Green Cyano
You can go lights out 3 total days.
You can keep waving it away with a power head or a wave of the hand. Try and get some better flow in that area for the time being, it should go away with keeping on it.