And I see that you've been paying attention to the moisture content. I would consider switching when you can to another method. The pf tek is just throwing cakes in to grow right?
Buy a rubbermaid tote, cut four holes on two sides opposite each other. The bigger sides. The holes should be about 2 inches wide, and there should be two near the bottom where the top of the cakes/substrate will be and two should be near the top. Then stuff polyfill (2 bucks for a bag at craft stores) into the holes. Then you cut out a big rectangle in the lid, slap some clear plastic over it to make it airtight but let light through, and you have a growing chamber. With a base of wet perlite the humidity should go sky high, then you adjust a fan to blow on one side of it so the air and humidity slowly go out the polyfill. The polyfill is perfect because it doesnt wick moisture. I would do this but then make the entire base of the rubbermaid my substrate. Pulled lots out of these things back in the day.
What is in the PF tek again? I have used birdseed almost exclusively because it is so much easier than anything I tried early on.