Shrooms only require 4-6 hours of light a day. It doesn't matter what light, whether direct or indirect, natural, flourescent, or incandescant. The light is only used to let the mycelium know to start forming pins, and to let the mushrooms know in which direction to grow. The light isn't actually used like a plant would.

You probably need to make sure you are airing out the chamber enough. Since you are using perlite, all that extra hand-spraying is unnecessary. What I'd do is air out the terrariums twice a day. Spray right after to get the humidity back up, and the perlite will maintain 100% humidity until you air it out again.

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"A good shroom is like a 'sore' peter...You just can't hardly beat it"