I grow in a closet and hydro seemed easier than soil to me. Is it tho...hard to say. Took a couple grows but I got it down now. I'd probably say coco is the easier option. I do a flood drain in clay balls.
Id go with the bleach route if you want to be 100% sure you will never have a problem.
Most likely you got some bacteria on your hand and then transfered it into the system. It happens. Happened to me. That is why I went with a sterile system.
Chopping my latest run as it matures.
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