Many materials can be used to pot Phalaenopsis orchids as long as they provide proper drainage and root aeration. While orchid bark and sphagnum moss are the two most popular orchid potting materials in the U.S., they are usually mixed with a number of other materials to create commercial (or homemade) potting mixes. See below for some common concerns that come up about the soil and media orchids are potted in.
The white substance in your soil is most likely from over-watering or not enough air circulation. Withhold watering your orchid until the orchid roots are grayish-white in color. You may then resume watering your orchid with 3 ice cubes weekly. Mold is harmless to your orchid, but you should allow the plant to air out before watering again. It should also be noted to use distilled water to water your orchids. If you do use tap water to water your orchids, the white substance can be mineral build up left behind.
These insects may be living on decaying matter that can be found in the media. The best preventions are to be sure that the media is not too wet and to empty any extra water in the bottom of the decorative pot after each watering, as orchid roots should not sit in excess water. If you find bugs, you should isolate your orchid immediately from your other house plants. Once isolated, you can begin caring for the issue.
You are observing "air roots". These roots absorb moisture and carbon dioxide from the air, and can be left alone. Often times though, in the home, these roots shrivel up due to lack of humidity. You can remove the shriveled air roots with a sterile knife or scissors.