I purchased a prefabricated vinyl indoor greenhouse to grow my Nepenthes and other cps in. I have had this greenhouse for about 1 week. I was not using a fan and developed some black mold on some of my Nepenthes' leaves. It was suggested that I wipe off the mold and use a fan to prevent this. I had been leaving part of the greenhouse open to help with circulation, but this obviously did not work.
I have not been able to find a small fan to use in this indoor greenhouse. The greenhouse is 28"Lx19"Wx5'H. I currently am using a small clip on desk fan for circulation. This is the same one I had blowing onto the greenhouse, but it has now been moved inside and turned to low speed.
I have read that computer cooling fans can be used, but local suppliers are out of the 120V fans at this time.
What other types of fans are people using to circulate the air in their terrariums and greenhouses?