====== chlorine ======

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Properly managing chlorine is a key aspect of fishkeeping to ensure the health and well-being of your aquatic pets. Always use water conditioners when setting up or maintaining your aquarium to avoid any adverse effects on your fish.
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Chlorine is commonly used in municipal water supplies to disinfect drinking water, but it poses challenges for fishkeeping because it is harmful to aquatic life. Here’s what you need to know about chlorine in the context of fishkeeping:

  - **Toxicity**: Chlorine is toxic to fish and other aquatic organisms. Even small amounts can cause stress, damage gills, and impair the ability of fish to breathe. High levels can be lethal.
  - **Detection**: Chlorine is usually found in municipal water supplies, and its presence can be detected with water testing kits. It’s important to check your water source to ensure it’s treated properly before adding it to your aquarium.
  - **Dechlorination**: To make water safe for fish, you need to remove chlorine before adding it to the tank. There are a few methods for dechlorination:
    - **Water Conditioners**: These are commercial products specifically designed to neutralize chlorine (and often chloramine) in tap water. They work quickly and are essential for any fishkeeper.
    - **Aging Water**: While this method can remove chlorine, it is not always effective with chloramine, which is more stable. For chlorine, letting water sit for 24-48 hours can help it dissipate, but this is less reliable and practical compared to using water conditioners.
  - **Water Changes**: Whenever you perform water changes, whether partial or full, make sure to treat the new water with a dechlorinator. This is crucial for maintaining a healthy tank environment.
  - **Types of Dechlorinators**: Some dechlorinators also detoxify chloramine and heavy metals, providing additional protection for your aquarium. It’s a good idea to use products that cover a broad range of potential contaminants. [[[:products:seachemprime|Seachem Prime]] is one of the best products that will detoxify a broad range of contaminants.
  - **Impact on Biological Filtration**: Chlorine can harm beneficial bacteria in your aquarium’s biological filter, which play a key role in breaking down fish waste and other organic matter. By using dechlorinators, you help protect these bacteria and maintain the balance of your aquarium’s nitrogen cycle.