Care
A spacious, mature well-filtered tank is necessary for these large, stout fish. In the wild, they are found in a variety of habitats including rivers, swamps, and floodplains with muddy or silty substrates, often among dense aquatic vegetation or the cover of undercut banks. Therefore, the aquarium substrate should consist of soft sand, and there should be ample resting places such as pieces of driftwood, caves formed from rocks/pieces of slate, and scatterings of cobbles/small pebbles. Dim lighting is preferential. Hardy vegetation may be left alone by juvenile specimens, but adults will uproot and feed on many aquatic plants. This species can be maintained in groups, providing there is an abundance of visual barriers amongst the décor, and that the tank itself is roomy, otherwise they may bicker over territories. Tankmates should be peaceful and of a similar size, as adults will prey on small fish. Despite the adult proportions of G. margaritacea, it is a fish that is easily bullied by belligerent fish of similar size, so choose tankmates with care. Ensure that the aquarium has a tight fitting cover as these fish will jump. Several geographical colour forms of G. margaritacea are known, some being extremely vibrant. May also be seen on sale as the Snakehead Gudgeon.
Feeding
These gudgeon require a variety of foodstuffs, both meaty and vegetable-based, appropriate to their size. Smaller specimens will enjoy daphnia, mosquito larvae, and Spirulina/vitamin-enriched brineshrimp, plus small sinking pellets and good quality flake/crisps. Move on to bigger foodstuffs such as Mysis, krill, larger sinking pellets etc as the fish grow. Do remember to include a vegetable component to the diet for best long-term health.
Breeding
Like many gudgeon, G. margaritacea has a pelagic marine larval stage, which makes successful rearing of fry very challenging in the home aquarium.
