How do I know when my cycling is done

[joshkamay]

Ammonia and nitrite are 0 and nitrate are about 5 just getting ready to do a 10 - 15 gal water change I have a 65gal with a 20 gal sump
So I'm just wondering what the next sign is in cycling or if its done cycling it has algae growing and everything
It looks like this currently
From what I've read its since cycling but I just wanna make sure