Compatibility Report
GuideMyTank compatibility analysis for Common Goldfish and Oscar.
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.
Common Goldfish and Oscar receive a conditional verdict from the current structured assessment. Common Goldfish is recorded as peaceful with an aggression level of 1/10; Oscar is recorded as aggressive with an aggression level of 6/10. The recommendation is based on the combined water, space, behavior, grouping, and predation checks below rather than on species names alone.
Common Goldfish has a recorded temperature range of 60–75°F and pH range of 7–8.4. Oscar is recorded at 74–81°F and pH 6–7.5. Their shared planning window is 74–75°F for temperature and 7–7.5 for pH. A shared aquarium must stay inside the overlap rather than merely touching each species’ outer tolerance.
Common Goldfish sets the larger listed base aquarium requirement at 75 gallons; the other listed minimum is 75 gallons. Oscar is the larger adult by the recorded maximum, reaching 14 inches, compared with 12 inches. These figures are starting constraints, not a stocking-capacity calculation, because the complete group sizes and bioload still matter.
Common Goldfish is a moderate species associated with the mid zone and moderate flow. Oscar is moderate, uses the mid zone, and has a moderate flow preference. Common Goldfish does not have a recorded minimum school larger than one, while oscar does not have a recorded minimum school larger than one. The aquarium must support both social structures without forcing either species into insufficient space.
Common Goldfish is recorded as a omnivore with easy care, while Oscar is a carnivore with intermediate care. Their listed preferred tank styles are goldfish and predator. 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 Common Goldfish and Oscar.