Azolla caroliniana

About This Species

Basic Description

Carolina Mosquito Fern, also known as Fairy Moss, is a tiny floating plant perfect for beginners. It is very easy to care for and thrives without special equipment. This plant grows quickly on the water's surface, forming a dense mat that helps control algae by blocking sunlight and absorbing fish waste. Because it multiplies so fast, you will need to regularly remove some to prevent it from covering the entire surface, ensuring light can still reach any plants below.

Detailed Description

Azolla caroliniana is a versatile floating fern ideal for low-tech setups with still or slow-moving water. Its rapid proliferation is a key feature; under sufficient light, it effectively outcompetes algae for available nutrients, significantly improving water quality and clarity. The fronds, which are typically green, can develop an attractive reddish hue in intense lighting. Its dense surface mat provides excellent shelter for shy fish, invertebrates, and fry, while also shading the tank below. Regular culling is essential to manage its spread and ensure proper light penetration and gas exchange at the surface.

Scientific Description

Azolla caroliniana, a member of the Salviniaceae family, is a free-floating aquatic fern. Its most significant biological feature is its symbiotic relationship with the nitrogen-fixing cyanobacterium Anabaena azollae, which resides in cavities within the fern's dorsal lobes. This symbiosis allows the plant to efficiently convert atmospheric nitrogen, contributing to its rapid growth and high capacity for nutrient sequestration from the water column. This makes it an effective agent for bioremediation. Morphologically, the plant consists of small, overlapping scale-like fronds on a branching stem, propagating primarily through vegetative fragmentation in aquarium settings.