water chemistry

Cycling the Tank

Establishing the nitrogen cycle

What does Cycling the Tank mean?

Cycling is the process of growing the bacterial colonies that convert ammonia → nitrite → nitrate. Required before adding fish to any new tank. Takes 2-6 weeks depending on method.

How is Cycling the Tank used in aquariums?

Methods: fishless cycle (dose ammonia + bottled bacteria, 2-4 weeks), live rock cycle (saltwater only, 4-6 weeks). NEVER skip - adding fish to uncycled tank = ammonia poisoning + dead fish.

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Frequently asked questions

What does Cycling the Tank mean in fishkeeping?

Cycling is the process of growing the bacterial colonies that convert ammonia → nitrite → nitrate. Required before adding fish to any new tank. Takes 2-6 weeks depending on method. Methods: fishless cycle (dose ammonia + bottled bacteria, 2-4 weeks), live rock cycle (saltwater only, 4-6 weeks). NEVER skip - adding fish to uncycled tank = ammonia poisoning + dead fish.