Algae on fox farms ocean forest soil

Hey all, so about a week ago I noticed just a small amount of algae growing on my soil. I googled it and read about many options to try and kill it… h2o2, bleach, blocking the light to the soil, letting it dry out, adding 1 inch layer perlite over soil, etc. I decided to let it dry out(5days) and cover the top of my soil with perlite. I realize I caused the problem most likely by over feeding(rookie grower) and now I know. However, my plants are due for a feeding tonight and I still have my soil covered with the perlite in the affected pots. I don’t know if I should remove the perlite or water my plants and let it continue to stay there. Does anybody have any recommendations on how I should proceed…?

You can still feed through the perlite. Shouldn’t really cause any problems

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I was thinking I would just carry on as is, thanks for the reassurance!

The perlite will go green too.
What would work the best is mulch.
I use my chopped cover crop on my 20g fabric pots.
On the smaller 1g fabpots I used chopped up barley straw.
Keeps the soil moist and microbes and worms happy.
You could also ignore the algae. Won’t harm anything.

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you transplanted a bit early, the soil is getting more light than the plant. ergo you have stuff growing on the soil.

Let it be. it keeps moisture in. It hurts nothing that im aware of , it goes away when the plant covers the light.

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Like Wheels84 mentioned, you can feed through the perlite just fine.

Overall, I wouldn’t be too concerned about the algae, it is very common and not harmful. With time, the perlite will likely begin to grow algae as well.

I would focus on the cause of the algae instead of trying to eliminate it. How are you deciding when to feed? It looks like you may have recently transplanted into larger pots and it is likely the root system hasn’t fully established and chances are you are over watering which is not good for your roots.

Cannabis plants prefer long wet-dry cycles so you are going to want to get good at understanding the sweet-spot on water timing which can only really be learned with experience (not a predefined schedule). The best rule of thumb is to go by weight of the pot, if it feels heavy at all, they can go another day. A secondary test is getting index-finger deep, if it’s moist at the tip-- they aren’t ready to be watered.

The ideal time to water is right before they start drooping (when the soil is 0% damp). The drooping occurs as the plant starts using it’s reserve water stored in it’s leaves. IMO, it is worth letting them get to the droopy once so you get a better understanding of how long they really need between waterings.


Hey tosi, so yes I did transplant those lil guys into 5 gal fabric pots, about 14 days after being in a red solo cup. Maybe I should have waited a little longer in the solo cup? Or maybe should have transplanted in a smaller pot? As far as when to feed that’s something that I was having trouble with early on. I was watering about every 2-3 days and realized that was way too soon, I now water every 4-5 days using about 80% of a 1 gallon jug. I lift the pot to see how light it is and when it feels very very light/soil is dry I’ll water again. I feel like I still need to get better at this but it is definitely better than how I was first watering. One of the main things I’ve been confused on is if I should water till water run off every time? At first I was but then I stop watering till runoff cause I wasn’t sure. I use fox farm ocean forest soil along with their trio nutrients every other watering.

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And I always make sure my ph is btwn 6.3-6.8

I start in solo cup… 2 wks into 1gal. 2 more wks 3gal. Another 2 weeks and I flip the lights

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