Contamination Prevention: A Complete Troubleshooting Guide
38 replies · Cultivation Science
I'm putting together the most comprehensive contamination guide I can. Please share your contamination experiences and solutions — what type, what caused it, what fixed it. I'll compile everything into a definitive resource. Types I want to cover: green mold (trichoderma), cobweb mold, bacterial blotch, black pin mold, and the weird yellow/red metabolites that look like contamination but aren't.
Green mold (Trichoderma harzianum and relatives): the most common and aggressive. It spreads via airborne spores and thrives in the same conditions as cubensis. Prevention is everything — treatment is not reliable once established. Root causes: poorly sterilized substrate, contaminated spawn, poor SAB technique, opening containers before full colonization. If you see a spot of green: isolate immediately, do not open the container in your grow space.
Cobweb mold (Hypomyces and relatives): looks like very fine, wispy white strands, distinctly different from mycelium. Unlike trichoderma, cobweb mold responds to increased FAE — if you fan the container twice daily and increase air exchange, cobweb often recedes on its own. Mycelium continues to grow through it. Not always a death sentence for the grow.
Bacterial blotch: wet, slimy, brown patches with a foul smell. Usually caused by over-moisture — condensation dripping onto substrate, over-misting directly on substrate, or not draining field capacity properly. There's no saving a contaminated substrate from bacteria — the same conditions that cause it will reinfect. Dispose, sterilize container, improve moisture management next run.
35 more replies — forum posting coming soon.