Nitrogen Cycle

The Nitrogen Cycle (The Most Important Thing of All)

The nitrogen cycle is the most critical biological process in any aquarium. Without understanding it, it is impossible to maintain a healthy aquarium.

The Step-by-Step Process

Nitrifying bacteria

They are the "biological filter." They live in:

• The filter media (sponges, porous ceramic, bioballs)
• The substrate at the bottom
• Decorations (rocks, roots)
• To a lesser extent, in water

It takes 4–8 weeks for them to colonize a new aquarium → this is what we call "breaking in" the aquarium.

Why Do Bacteria Die?

• Chlorine in tap water (always use a water conditioner)
• Clean the filter with tap water
• Antibiotics or Medications in the Water
• Drastic temperature changes
• Lack of oxygen (they need O2)

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