How to Dark Start/Cycle an Aquarium

The ‘Dark Start’ is exactly as it sounds. Cycling an aquarium in the dark. This is a method that we highly recommend to anyone starting a planted aquarium for a few reasons.

  1. Less algae
  2. Less plant melt
  3. Safe introduction of fish


How to Dark Start an Aquarium

  1. Fill your aquarium with desired substrate and hardscape. Ensure wood is waterlogged or attached to rocks to prevent it from floating when the tank is filled.
  2. Fill your aquarium, making sure to add a Dechlorinator such as AquaLabs Vitality
  3. Turn on your filter and heater.
  4. Add a source of ammonia to kick start the aquarium cycle. If you are using an aquasoil you will not need to add anything as most aquasoils release ammonia in the first weeks of use. If you are using an inert substrate such as gravel or sand an ammonia source will need to be added. This is best done using an aquarium specific ammonia additive.
  5. Don’t turn your lights on and wait. Using aquarium test kits for ammonia, nitrite and nitrate you can monitor the progress of the cycle. When ammonia and nitrite have zeroed out and nitrate a reading is present, the aquarium is cycled and fish and plants can be introduced.
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