A reader asked where one might be able to purchase small, tropical aquatic worms. Presumably this would exclude the giant tube worm, which lives near undersea volcanic vents and can grow to over seven feet in length. However, for the buyer interested in purchasing tropical aquatic worms of the smaller variety, a number of options abound.

Tropical marine worms are a diverse group of organisms encompassing several different taxonomic groups. Depending on your fancy, you may be interested in purchasing flatworms (phylum Platyhelminthes), roundworms (Nematoda), segmented or “fan” worms (Annelida), arrow worms (Chaetognatha), or another of the great variety of worm species that live in aquatic habitats. Unlike the previously mentioned giant tube worms, members of all of these worm phyla tend to be quite small (although exceptions exist), and most of them thrive in tropical marine habitats.

For the most frugally-minded consumers, it’s quite likely that just by owning and maintaining an aquarium you will acquire a healthy population of planaria worms—tiny, white flatworms that naturally populate many marine environments. Don’t worry, they won’t harm the fish, but they sometimes show up when your aquarium has too much gravel containing too much uneaten fish food.

If planaria aren’t your style, however, it’s time to select the size and shape of worm that suits your preferences. Once you’ve picked the tropical aquatic worms you’d like to purchase, a logical first step would be to visit your local fish and aquarium supply store and see if anything from their selection of worms matches what you had in mind. If you are still unsure of which type of tropical aquatic worms you would like, the people who work there may be able to help you make your decision by showing you examples of different tropical aquatic worm species. Should no local store have what you’re looking for, it is not unheard of for online vendors of fish and other aquarium supplies to dabble in aquatic worms (yes, it is possible to ship live sea creatures and have them arrive alive!).

In short, if you would like to buy small, tropical aquatic worms, you will likely find a decent selection of them at aquarium supply stores or wherever live fish and other sea creatures are sold.