These cast acrylic red plates will fit over the Mini Hearth modular formicaria. There are holes that slide over the magnets and the plates are thick enough to hang on the magnets easily.
Why use them? Some ant species, such as Formica subsericea here locally (and other Formica spp. particularly), are very prone to being alarmed when lights become suddenly brighter around them. The Darkscreen Plates will filter out a large amount of light. This potentially benefits the colony in that it keeps them more relaxed during maintenance and feeding.
Once the plate is removed and light is allowed into the formicaria, allow 10-15 minutes for the colonies to adjust to the light changes and resume normal activity. This waiting period may be necessary when planning photo and video sessions.