Just a harmless aquatic worm, most likely Tubifex worms. Means your tank is healthy. They come in on the roots of plants and eat anything organic in the substrate (fish food, fish waste, etc).
Camallanus worms only grow to about 10mm (less than 1/2 inch) maximum.
Detritus worms are usually white or cream and grow to about 6mm (1/4 inch).
Camallanus worms only grow to about 10mm (less than 1/2 inch) maximum.
Detritus worms are usually white or cream and grow to about 6mm (1/4 inch).