Tank stocking ideas

125-gallon tank stocking ideas

3 themed stocking plans with exact species + counts + notes. Pick the theme that fits your goals, then verify with the stocking calculator.

3 themed stocking ideas for 125-gallon

1. Premium reef + full tang school

  • 1x Yellow tang
  • 1x Purple tang OR Powder blue tang
  • 1x Kole tang
  • 1x Pair Designer clownfish
  • 1x Six-line wrasse
  • 1x Pair Banggai cardinal
  • Full SPS + LPS + soft coral

Notes: Multi-tang setup. 6-foot length disrupts territorial overlap. Premium LED + flow + ICP-tested water.

2. Adult oscar pair + community

  • 1x Pair Adult oscars
  • 4-6x Silver dollars
  • 1x Pair Severum (firmouth or red)
  • 2x Common pleco

Notes: Big-fish display tank. FX-series + sump + heavy filtration. Largest practical home oscar setup.

3. Adult arowana

  • 1x Adult arowana (silver, black, or red)
  • 4x Silver dollars (dither)
  • 6x Bichirs as bottom dwellers
  • 2x Cleanup pleco

Notes: Show-quality arowana display. 72" gives the fish room to swim. Tight-fitting lid mandatory - arowana jump.

Verify your stocking plan

Use the stocking calculator to verify the exact species + counts work in your 125-gallon. Also check the water change calculator for ongoing maintenance, and the setup guide library for the full build playbook.

Other tank sizes

Browse all stocking idea pages from 5g nano to 180g show-tier. Or jump to the stocking blueprints for build-along plans with timelines.