FastAquatics
Tank stocking ideas

90-gallon tank stocking ideas

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

4 themed stocking ideas for 90-gallon

1. Premium mixed reef

  • 1x Pair Designer clownfish (Snowflake or Frostbite)
  • 1x Six-line wrasse
  • 1x Royal gramma
  • 1x Banggai cardinalfish pair
  • 1x Yellow watchman goby + tiger pistol
  • 1x Tang species
  • Full SPS + LPS + soft coral

Notes: The vertical depth (24") allows tower-style aquascape with multiple light zones for SPS at top, LPS at middle, soft at bottom.

2. Mbuna cichlid full setup

  • 30-35x Mbuna mix (8-10 species)
  • Holey limestone structure
  • Aragonite sand

Notes: Larger species options open up at 90g - red zebra, demasoni, johanni, acei, yellow lab. Intentional overstocking + 30% weekly water change.

3. Discus colony

  • 8-10x Adult discus (multiple lineages)
  • 15x Cardinal tetras
  • 8x Corydoras sterbai
  • 4x Bristlenose pleco
  • Heavily planted with bare-bottom or sand

Notes: German breeder discus collection. Daily 25-50% water changes during growth. RODI + remineralization.

4. Large planted display

  • 25x Rummy nose tetras
  • 15x Cardinal tetras
  • 8x Corydoras
  • 6x Otocinclus
  • 1x Bristlenose pleco
  • 1x Pair angelfish
  • Iwagumi or Nature Aquarium aquascape with CO2

Notes: Show-quality planted tank. CO2 + EI dosing + premium LED. The plant biomass alone justifies the upgrade from 55g.

Verify your stocking plan

Use the stocking calculator to verify the exact species + counts work in your 90-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.