Appearance and growth habit
Riccia fluitans, commonly known as Crystalwort Moss, is a vibrant bright green liverwort that forms soft, branching cushions over rocks, wood, and other hardscape. Despite its common name, it isn't a true moss, but it creates the same lush, carpeted effect that terrarium and aquascaping enthusiasts love. It naturally grows by spreading into dense mats, making it ideal for adding a fresh, rainforest feel to humid displays.
 
Care requirements
Crystalwort thrives in bright, indirect light, consistently high humidity, and constantly moist conditions. It can be grown floating in aquariums or attached to rocks, driftwood, or mesh in terrariums and paludariums. Keep it from drying out, trim it occasionally to encourage dense growth, and provide good airflow to keep it looking its best. A little haircut every now and then keeps it neat and happy.
 
Troubleshooting
Brown or crispy patches usually mean the plant has dried out or humidity is too low, while pale growth often indicates insufficient light. Thick mats can trap debris over time, so regular trimming helps keep the plant healthy and vibrant. Crystalwort is rarely troubled by pests, although poor airflow may encourage algae or fungal issues in overly damp setups.
 
Pet and reptile safety
Riccia fluitans is considered non-toxic to cats, dogs, and people. It is also an excellent choice for humid reptile, amphibian, and invertebrate enclosures, where it provides natural cover and helps maintain humidity. While safe as a decorative plant, it should not be relied upon as a food source, and only pesticide-free plants should be used in animal habitats.