Should I be concerned about this mold?

[gjjdemarco]

Hello all,

I am new here as well as new to hydroponic gardening.

First of all, thanks to all the members here who I have used as inspiration for building my first ebb & flow system. I will put together some pictures and particulars soon.

I am hoping some of you pros out there could tell me if I am being overly cautious though about some mold.

Situation is as follows: I have a bunch of pepper plants in an ebb/flow tray. Well lit, low heat. 6" net pots that get their water automatically once/day. fills to about 5" level of the 6" pot.
The growing medium is 2/1 perlite/vermiculite, then mixed 4/3 hydroton/PV mixture if that makes sense.
Plants seem to be growing accordingly, but I noticed today that I see some green on my medium. Noticeable really only on the perlite as it is white.

I don't have very good air flow though as it is in my garage and it has been incredibly humid around here the last couple weeks.

I plan on getting an oscillating fan on a timer to run about 15 mins every 2 hours or so. Will that help? Should I be worried?

Sorry for the long post.

[GpsFrontier]

Hello gjjdemarco,
Even thought pictures would be helpful, from your description of water level and where you notice it growing, I don't believe it's mold. I would guess it's algae. Algae is a micro flora (tiny plants). First it won't really hurt your plants, it can use dissolved oxygen in the water the plants need, but you would need a lot of it to make any difference. Algae needs 3 things to grow. 1. water/moisture. 2. food (like nutrients in the nutrient solution). 3. Light (that's why it's growing on top of the growing media). You need water and nutrients for the plants to grow. But you can adjust the water height so the very top of the growing media stays dry while still keeping the root ball moist. Also you can just cover the top of the growing media with cardboard, Styrofoam, or plastic lid to block light. If it doesn't go away (die of) shortly after you block the light from it, then it's not algae and some type of fungi (mold is a type of fungi).

P.S.
Humidity is good for plants even up to 80%-85%, however without good air circulation it can easily cause fungal spores to germinate in areas that stay wet all the time. Usually this happens on the plants foliage, and the fungi feeds on the plants leaves. Good air circulation will also be beneficial to help pollinate plants like peppers and tomato's. An oscillating fan is a good idea, but I would let it run 24/7 and make sure it covers the entire plant area, or get enough fans so it does.