Meet the bottom-dwelling fish

Fish that feed near the substrate still need suitable water, enough room, safe surfaces and food designed for them. They do not live on scraps alone, and adding them will not solve excess algae or poor water quality.

Provide open floor space as well as shaded retreats. Choose substrate and decor that suit the species, and keep the bottom clean without making the habitat bare or stressful.

Corydoras catfish are active little foragers that often rest together and explore the floor in a group. Their barbels help them search through the substrate, so a smooth, fine aquarium-safe surface is a thoughtful choice. Keep the floor free of sharp fragments and give them places to shelter.

Species differ in adult size and preferred conditions. Check the needs of the exact corydoras species you are considering, provide an appropriate group, and make sure food reaches the bottom rather than being taken by faster tankmates.

“Pleco” covers many species, from smaller aquarium residents to fish that grow far too large for a typical community tank. Identify the exact species and plan for its adult size, diet and shelter before purchasing it. Algae growth is not a complete food source, and many plecos need a varied, species-appropriate diet.

Loaches also differ widely. Some remain small and sociable; others become large, energetic fish that need a spacious aquarium and companions of their own kind. Avoid buying a fish based on a juvenile’s appearance alone.

Offer an appropriate sinking food and observe feeding time. If the upper levels empty the food before it reaches the bottom, use a separate feeding point or adjust the method so slower fish are not outcompeted. Remove uneaten food before it breaks down and affects water quality.

For more about fish that use the open water, continue to midwater fish or surface feeders. Our compatibility guide helps you plan a balanced community.