We had two homes custom built for our sulcata babies & set them up last night. They are 2x2x4 box enclosures made of melamine & have a sliding plexi glass front. There are two vents in the top back corners & we drilled holes in the bottom part of the plexi glass for more ventilation. We have them stacked on top of each other to save on space. We have one 150 watt basking lamp on the left side & one 75 watt red heat lamp on the right side for night heating. There is a 24" uvb strip light hanging in the top front of the box. The substrate we are using is slightly moistened coconut fiber. In each box we have 1 water dish & a plate for food. There is one tupperware that we drilled a little door on the side & put vent holes on the top. We also put some rocks and fake plants to make it look more naturalistic. During the day we turn on the day bulb (left side) & the UVB strip light. At night the day bulb & uvb go off & the night lamp on the right turns on. When the day bulb is on the temp is 95 on the warm side & 83 on the cooler side & the humidity was around 75%. At night the temp was 75 on the right side (I don't remember the temp on the left side). When we woke up this morning we noticed what might be mold on the left side of the cage. Does anyone have any suggestions on what do to? Any I formation would be helpful.