I had green algae form on the soil of my 1st grow, but it didn't affect my leaves. I got rid of it by gently removing the top layer of soil with a spoon. I then made some covers for my pots that stopped light hitting the soil, so the algae was starved of light and couldn't grow.

Someone suggested a way I could remove it chemically...

Quote Originally Posted by tristan1986
A quick tip regarding the mold, hydrogen peroxide will remove the mold and also is a great fertilizer when used in small amounts. Check the below page for the exact amounts used, ive used their ratio when i had small amounts of mould on my clones and the results were spectacular!

Mixing charts for gardening with hydrogen peroxide
but the manual method worked for me.