sounds like staghorn...try a quick search to find other folks' remedies.
Here's mine: manual removal...or a 1:19 bleach:water dip. Either clip the infected leaves off...increase your co2...take a look at the EI dosing sticky in "water parameters" and see if you can get things back into balance.
If you choose the bleach method (its harsh)...don't dip the roots...just the leaves...wait for 30 seconds and look under a good light to see if the algae has turned orange...orange=dead.
good luck
Here's mine: manual removal...or a 1:19 bleach:water dip. Either clip the infected leaves off...increase your co2...take a look at the EI dosing sticky in "water parameters" and see if you can get things back into balance.
If you choose the bleach method (its harsh)...don't dip the roots...just the leaves...wait for 30 seconds and look under a good light to see if the algae has turned orange...orange=dead.
good luck