Is this just from algae?

[JKash]

Seasoned grower here... I am currently dealing with an issue I seem I just can't fix! I got a zkittlez a month into veg and the whole process has been really slow... I usually use Pro-Mix for my soil with halving the fox farm regiment... I had to use a different brand as pro mix is hard to find for some reason... I am now fighting algae on weekly basis even switching soil after soil brand after brand... I'm using a hydrogen peroxide water mix to flush soil with... any other ideas as to how to fight this

 

[Ponky]

Looks like it needed more perlite. Not drying out fast enough.

 

[JKash]

Looks like it needed more perlite. Not drying out fast enough.

Thanks! I have been totally over thinking the remedy...

 

[NorthernOrganics]

Yeah. Let the pot dry out between waterings.