Over the last few weeks, the algae in my 10G nano has been getting out of control. I clean the sides/fixtures one day, and the next they're coated in green algae again! There's all different colours - dark red (not coraline, although there is a tiny bit of that), light green strands, big thick clumps of dark green, some even black/dark brown. It's all over the rock, and even growing on my corals!
I have 3 fish - an ocellaris clown, purple dottyback, and a tiny yellow clown goby. I feed once a day, frozen, and wouldn't say I overfed.
The lights are 33w total, and are on for 10 hours a day (whites/actinic). My nitrates are around 20, so could do with being lower, but even after 5 PWCs they're not going down, so I think I have a problem with my test kit - I used the reference sample, and that was also out, so I wouldn't think the nitrates were the cause.
I use RO
water that I buy from my LFS
, and mix up 24+hours before I use it for a PWC
Can anyone help? This is driving me slightly insane