Invertebrates

Invertebrates are animals that lack (as you might guess) vertebrae--backbones. This is not a very meaningful distinction from a zoologist’s perspective, as it pretty much includes all animals except for one phyllum, Chordata, if not a single subphyllum, Vertebrata. Still, it is a somewhat useful distinction for aquarists, who tend to best understand the needs of fish (i.e. fellow vertebrates). Fish are very widely available and generally are relatively easy to maintain in captivity. They are active and reasonably (sometimes surprisingly) intelligent. We can even (at least to some extent) train them. Invertebrates, on the other hand, might seem a comparatively alien. Often, they don’t eat in the same manner that we do. They may require very special foods or lighting. They might be extremely fussy about certain water parameters (iodine, calcium, etc.). For sure, they might be a little intimidating for beginner aquarists. Worst of all, because they are such a diverse group (everything from sponges to octopuses to mantis shrimp!), they oftentimes require a lot of research and planning to keep successfully in captivity. All that being said, it is the sheer variety of marine inverts as a group that makes them so fun and rewarding to keep in aquaria. For sure, nothing can be more amusing for an aquarist to show their well-stocked reef tank to a non-aquarist friend/family member and get questions like, “Is that real?” or, ”Is that alive?” In this section, you will learn about the natural history of diverse invertebrate marine life and how to successfully keep each type in captivity.