Two answers · stocking

How many fish belong in here?

First Tank verdict. Aquarists add a few, wait, test, add a few. Living Oceans treats the included pack as the stocking plan and says the tank gets territorial as it matures.

Living Oceans source: recommended livestock limits on product pages; first-year guide — at six months “introducing new fish is challenging due to territories.” Aquarist source: ignore inch-per-gallon; adult size; school of 6+ needs room for 6 adults.

Normal aquarist answerLiving Oceans answer
Opening stockAlmost none until the cycle ends.The included animals after the system is running.
Adding laterSlowly, if tests stay clean.Harder after social structure sets (~6 months in their timeline).
CeilingYour test kit and the adult size chart.That model’s published livestock limit.
Complete system · not a glass box Stay inside their recommended livestock limits

By six months they warn territories make new fish difficult.

See the system limits

First Tank may earn a commission. Living Oceans answers are taken from Living Oceans’ own guides, product pages and care checklists. Normal aquarist answers are standard hobby practice — not one shop.

Ask next: Which fish

Skip the 20L kit. See the complete clownfish system.

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