What's eating my waterwheel plant?

Waterwheel Plant (Aldrovanda vesiculosa) is a fully aquatic, rootless carnivore and virtually immune to typical houseplant insects. The main threat is algae overgrowing and shading out the stems. Aquatic snails may occasionally browse the plant; mosquito larvae from stagnant water are a secondary nuisance requiring screening.

Green or blue-green algae coats stems and traps, blocking light and suffocating the plant; growth stalls and stems brown Use only pure rainwater or distilled water with zero fertiliser; reduce photoperiod to 10–12 hours; physically remove algae and introduce Daphnia water fleas to graze it; cover the container to block direct sunlight

Snails browse delicate trap whorls and stems, leaving ragged edges; infestations in aquaria can rapidly defoliate the plant Remove snails by hand daily; introduce only pest-free water sources; avoid adding pond water that may carry snail eggs or juveniles

Larvae develop in the standing water container, competing for microorganisms the plant feeds on; adults emerge as a household nuisance Cover the container with fine mesh screen to trap and drown adults while allowing light in; BTi dunks (Bacillus thuringiensis israelensis) in the water are safe for the plant