Compatibility Report
GuideMyTank compatibility analysis for American Flagfish and Brilliant Rummynose Tetra.
Planning verdict
cautionOnly plan this pair if every listed condition can be met, and have a separation plan if stress or aggression appears.
No automatic safety blocker was found.
American Flagfish and Brilliant Rummynose Tetra receive a conditional verdict from the current structured assessment. American Flagfish is recorded as semi-aggressive with an aggression level of 4/10; Brilliant Rummynose Tetra is recorded as peaceful with an aggression level of 1/10. The recommendation is based on the combined water, space, behavior, grouping, and predation checks below rather than on species names alone.
American Flagfish has a recorded temperature range of 64–78°F and pH range of 6.5–8. Brilliant Rummynose Tetra is recorded at 75–82°F and pH 5.5–7. Their shared planning window is 75–78°F for temperature and 6.5–7 for pH. A shared aquarium must stay inside the overlap rather than merely touching each species’ outer tolerance.
American Flagfish sets the larger listed base aquarium requirement at 20 gallons; the other listed minimum is 20 gallons. American Flagfish is the larger adult by the recorded maximum, reaching 2.5 inches, compared with 2 inches. These figures are starting constraints, not a stocking-capacity calculation, because the complete group sizes and bioload still matter.
American Flagfish is a moderate species associated with the mid zone and low flow. Brilliant Rummynose Tetra is moderate, uses the mid zone, and has a moderate flow preference. American Flagfish should be planned as a group of at least 2, while brilliant rummynose tetra should be planned as a group of at least 8. The aquarium must support both social structures without forcing either species into insufficient space.
American Flagfish is recorded as a omnivore with intermediate care, while Brilliant Rummynose Tetra is a omnivore with intermediate care. Their listed preferred tank styles are community and blackwater. Feeding access, cover, open swimming room, filtration, and observation should be planned around the more demanding requirement rather than averaged between the two species.
Use these pair-specific boundaries before treating the verdict as an acceptable stocking plan.
Only plan this pair if every listed condition can be met, and have a separation plan if stress or aggression appears.
These references support the underlying species records used by this assessment. They do not necessarily evaluate this exact pair together.
Continue with the most relevant care and compatibility resources for American Flagfish and Brilliant Rummynose Tetra.