Green mould, moss or fungus?

On top of my coco a green type moss or mould is starting form, Should I be worried?

Been watering every other day in 6.5 litre pots, plants are 5 weeks old. Would bottom feeding by putting the plants on a tray with water on help? Temps around 77-80F under a 400w HPS, Humidty 35-45%

Thanks

Cover the top of the grow medium with something opaque and it will die.

Cheers bluefish, Anything inparticular? Like would white card be sufficient

+rep

Johnou833 said:

Cheers bluefish, Anything inparticular? Like would white card be sufficient

+rep

Click to expand...

Anything that light can't penetrate is fine