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Could use a little info on water paramaters; ammonia, nitrate,nitrite, SG, pH, water temp, calcium. If you are monitoring these items, I see no need to go through the expense of sending your water to some sort of lab. If you are using tap or well water, stop. RO water is the only way to go. What about lighting? I find my mushrooms do best slightly under an overhang, so that they are getting more indirect than direct lighting. That is really all I can say at this point, with the limited info given.