Algae playing havock

[Ballinlea]

How can I get rid of this? Playing havoc in my sump. This is on my skimmer. Emerald crabs???
I only have it in my sump. Had it build up in the outlet pipe of my reactor and a lump of it lodged in the intake of my skimmer. Have removed quite a bit of it in the past.
It is quite firm, forms clumps and comes away fairly easily.
Thanks.

 

[TX_REEF]

the easiest way to get rid of and prevent this is to not let light spill anywhere you don't want it in the sump. Algae will certainly grow wherever sufficient nutrients and light are present

 

[E.R.A.]

Easiest way like you did manually remove it. Its a nutrients sponge that you don't want to grow obviously. Do you have a refuge? I wouldn't recommend EC because once the food is gone you still need to feed them. I think fixing the issue that is causing the macro algae to grow is first. You seem to have an excess of nutrients it likes.