IMO

I am trying to make an IMO collection for my green house cannabis grow. my last IMO had pink spots, it did sprinkle one day , though I had a tarp it could have gotten wet.  After reading about someone else saying they had same problem i realized that I probably shouldn’t use that collection.

What is the best the location for creating an IMO for greenhouse? by soil yard? next to the greenhouses out side. I am not sure how healthy the hedgerow plants are next to the green houses but there is a lot of mycelium and leaf mold growing in the soil. I guess I will try using even less water for making the rice, because I usually get a few spots of pink, and I thought it was good diversity, but from what I have researched it seems that is not true and white fluffy collection is ideal.

Another question, can IMO be stored in the fridge?