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Where rivers meet the sea.

The brackish rhythm.

Brackish keeping is about salinity discipline. Match the salinity of replacement water before it goes in, and let the estuary rhythm — partial changes, tannin refresh, root growth — become part of your routine.

🌡 75–82°F🧂 Specific gravity 1.005–1.010💧 20–25% every two weeks

Daily

A few quiet minutes

  • Top off with appropriate freshwaterEvaporation raises salinity — top off with freshwater and let the gradient settle.
  • Check salinityTypical brackish range: specific gravity 1.005–1.010.
  • Check temperatureTypical range: 75–82°F.
  • Observe fish behaviourWatch for aggression and stress — brackish communities need territory and cover.

Every Two Weeks

Water changes & cleaning

  • Perform a 20–25% water changePrepare replacement water separately and match salinity before adding.
  • Vacuum the substrateEstuary substrates trap waste — siphon the surface layer.
  • Clean the aquarium glassSoft algae films are normal; keep the viewing panes clear.

Monthly

Testing & deeper maintenance

  • Monitor ammonia, nitrite and nitrateSame safety targets: ammonia 0 · nitrite 0 · nitrate as low as practical.
  • Maintain filtrationRinse media in removed tank water; never untreated tap water.
  • Trim plants and mangrove growthPrune roots and leaves where appropriate — mangroves grow fast.

Test targets

Numbers to aim for when your test kit asks.

Specific gravity

1.005 – 1.010

Between fresh and marine

Ammonia / Nitrite

0 ppm

Always zero

Nitrate

< 20 ppm

Mangrove plants help consume nitrates

pH

7.5 – 8.5

Slightly alkaline, like an estuary

General guidelines — species-specific requirements override these numbers. Always research your specific livestock.

Ready to keep the rhythm?

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