A Congo tetra eats like a mid-sized river fish, not like the tiny tetras it shares a family name with. In the Congo River basin this schooling species takes insects from the surface, picks small crustaceans and worms from the water column and grazes soft plant material and algae, and adults grow large enough — with males carrying long, flowing finnage — that the diet has to carry real substance. The aquarium version is a three-part rotation: a quality flake or small floating pellet as the daily base, frozen or live insect foods such as bloodworms, brine shrimp and daphnia for animal protein, and a deliberate green component that many tetra keepers forget. Congos fed only rich meaty food grow prone to heaviness; Congos fed only flake lose the iridescent condition the species is kept for.
Running the three-part rotation
Anchor the week on the staple, offered twice a day in amounts the school clears in about two minutes, and swap in frozen insect foods for one of those feeds several times a week, thawed and distributed across the school's whole length. Live foods, when available, are worth using for conditioning: a school hunting brine shrimp through open water shows the flashing, lateral displays that are this species at its best, and males colour most strongly on that varied ration. For greens, offer blanched shelled peas, softened spinach leaves clipped where the school can tear at them, or a spirulina-heavy pellet on the non-insect days. Keep individual pieces modest — Congos have good appetites but not huge mouths, and a male with fully extended fins is manoeuvring, not competing, so wide distribution matters more than large items. Young, still-silvery fish grow fastest on the protein-rich end of the rotation, while mature males hold their best shape when greens are genuinely regular rather than occasional.
Feeding a school with a hierarchy
A Congo school feeds as a ranked group. The biggest males arrive first and feed centre-stage, females and subadult males work the flanks, and food dropped in one spot becomes a contest the same fish always win. Release each meal in two or three places at once, or along the front glass in a line, and watch the edges of the school as carefully as the middle: every fish should leave the feed a little fuller. Tankmates matter here in both directions — Congos are peaceful but sizeable, and genuinely small fish can be intimidated out of feeding, while pushy fin-nipping species will shred the males' trailing fins during the excitement of a feed, so Congo tanks pair best with calm mid-sized companions. If the school's enthusiasm fades over days, or individuals hang low and refuse the staple, check water quality and temperature stability before blaming the menu; this is a river fish that notices deteriorating conditions early and shows it first at mealtimes.
Portion sense for a big tetra
The school's speed is a poor portion guide, because a healthy Congo group will look ready for a second meal immediately after a correct first one. Judge by bodies over weeks: males should look deep and solid without a bulging belly line, females gently rounded, and growth in young fish steady. Leftover food in a long Congo tank tends to collect at the downstream end and in plant bases, so feed at the calmer end and let the current carry a little food to the fish rather than the surplus to the filter. Logging the rotation — staple days, insect days, greens days — in KinsLe with Care Teams keeps this three-part diet intact when different people feed the school, each completed feed timestamped so variety survives busy weeks.