Pelagic Feeding
Pelagic feeding refers to the strategy of consuming food particles suspended within the open water column, as opposed to grazing along the substrate, rockwork, or other surfaces within a tank. Many reef fish, along with filter-feeding invertebrates and certain coral species, rely primarily on pelagic feeding, capturing plankton, small food particles, or broadcast food as it drifts through the water.
Understanding pelagic feeding helps reef keepers choose appropriate feeding methods and food types for species that specifically rely on this water-column feeding strategy rather than bottom-oriented or surface-grazing alternatives.
Why It’s Important
- Describes the natural feeding strategy of many reef fish and filter feeders.
- Informs appropriate food type and delivery method for water-column feeders.
- Contrasts with substrate grazing and other surface-based feeding strategies.
- Helps explain why broadcast feeding suits certain species better than others.
How It Works
Pelagic feeders typically position themselves within the open water column, actively swimming to intercept food particles or, in the case of many filter feeders and certain corals, extending specialized structures to capture particles as water flows past. This strategy works well for species adapted to constantly drifting food sources like plankton, but requires food to remain suspended long enough to be captured before settling.
Broadcast feeding, where food is dispersed directly into the water column, is generally the most effective method for supporting pelagic feeders, since it mimics the natural drifting food sources these species evolved to capture.
Pelagic Feeding and Related Concepts
Pelagic feeding is closely tied to broadcast feeding, the delivery method best suited to it, and to plankton and ocean plankton, the natural food sources pelagic feeders typically target. It’s also relevant to filter feeders, organisms whose entire feeding strategy centers on this water-column approach.
Reef keepers stocking pelagic-feeding fish alongside bottom-dwelling or substrate-grazing species often need to consider feeding timing and distribution carefully, ensuring food reaches water-column feeders before settling to areas where it would primarily benefit different feeding types.
Filter-feeding invertebrates, including certain clams, tunicates, and non-photosynthetic corals, rely almost entirely on pelagic feeding for their nutritional needs, making consistent water-column food availability especially important for supporting these particular species.
Timing feeding to coincide with natural water flow patterns can also improve results for pelagic feeders, since food dispersed against strong directional flow may pass by too quickly for effective capture compared to a moment of gentler circulation.
Common Misconception
A common misconception is that all reef tank inhabitants feed similarly regardless of species. In reality, understanding whether a given fish or invertebrate is a pelagic feeder, a substrate grazer, or something else entirely is important for ensuring it actually receives adequate nutrition through appropriate feeding methods.
The Bottom Line
Pelagic feeding refers to consuming food particles suspended in the open water column, the natural strategy of many reef fish and filter feeders. Recognizing this feeding style helps reef keepers choose appropriate food types and delivery methods for these species.
