Aquatic Arts Marimo Aquarium Kit Includes 2 Marimo Moss Balls (1 to 1.5 inch each) while other kits only contain one. Includes a 38 ounce heavy glass authentic Italian swing top bale jar with vintage-style locking mechanism for the glass lid. Great and durable decorations for your home, office, or patio. Extremely easy to take care of. These moss balls can even live in tap water with a water change once every 2 weeks. No need for special lighting. Marimo Moss Balls grow very slowly, so the Marimo you receive are already about 5 to 6 years old. The 38 ounce jar included will be able to house them for over 10 years. Marimo are a fantastic gift for children to teach them about the responsibility of owning and taking care of a pet.