Whilst we love and care for our terrariums as best we can, depending on their new home and how they're cared for, sometimes things can go awry.
Below are some common issues and their remedies.
AIR, WATER, LIGHT
As terrariums are a warm, wet environment, sometimes mold can occur. Whilst frustrating, if it's dealt with early enough, mold is only a minor problem. Often mold occurs because there is too much water in the terrarium. Go easy on the watering! The best bet for removing mold is to take the lid off for a day or two to allow excess moisture to leave the terrarium.
Dead leaves or rotting plant matter can also be a cause for mold - be sure to remove any dead plant matter from the terrarium.
If the mold is occuring on an area that can't be cut away - like the soil - stir it up with a small tool to break it up and circulate air in the affected area.
If mold has taken over several plants or is affecting a large area of your terrarium, it might be best to remove the plants entirely.