One of the favorite indoor bonsai is the Chinese Banyan or Ficus mocrocarpa. Ficus are one of the best varieties of Bonsai trees for indoors. They're very easy to take care of and need little attention.
Light: As with any indoor bonsai the Chinese Banyan or Ficus Microcarpa will do best in bright light, but it will also survive under shade. For the best results grow the tree in the brightest location in your home and if possible augment the room illumination with artificial light. Ficus are very sensitive to movement and change in lighting and will protest being moved by dropping their leaves, so be sure to find a bright location and keep it there to maintain optimum bonsai health. Even fluorescent lights placed close to the foliage will be a great help in keeping the tree healthy and vigorous.
Water: Bonsai trees live in small pots and their world dries out much quicker than plants in the ground or in bigger pots, so close attention should be paid to watering. All ficus bonsai appreciate even moisture at the roots. Allow the soil surface to dry a bit before watering again. Roots kept constantly wet will rot.
Misting: Leaves want humidity to keep them green and healthy. Any time your tree is inside, the air is very dry. Mist often during the week.
Pruning: Pruning encourages new shoot growth and is best carried out during the warmer growing seasons. To maintain shape cut back to the last two leafs on shoots that have grown 5-6 leafs. When you trim a Ficus, it will bleed a milky, white sap—actually latex. This latex dries quickly and makes a great sealant. When pruning back smaller branches leave a short stub which will dry out over the following days, then just take the dry branch off and it will heal with less of a scar.
Repotting: You should repot your Ficus every two to three years in the spring using a basic soil mix. A good rule of thumb for repotting your Ficus is if you can remove the root/soil ball in one piece and it’s the same shape of the pot, it’s time. After repotting, water thoroughly and place Ficus in a shady location for several weeks so new roots can grow.