Aquarium Water

Fish eat, sleep, and breath in water 24 hours a day. Needless to say, water problems can be very serious for your fish. This guide covers all the key water problems and solutions.

Adding, Treating, Changing
Adding water is one of the first tasks when starting a new aquarium. Should it be treated and then added, or added and treated afterwards? Can tap water be used? What about changing the water? These articles answer all those questions, and then some.

• Bottled or Tap?
  
• Treating Water
  
• Chlorine and Chloramine
  
• How to Add Water to an Aquarium
  
• Aquarium Water Changes
  
• Do Water Changes Kill Fish?
  
• Using Salt in Aquarium Water
  

Water Chemistry 101
Although you don't have to become a chemist, understanding the basics of aquarium water chemistry will help you keep your fish and plants healthy. You'll find everything you need to know in these articles.

• Nitrogen Cycle
  
• Aquarium Water Testing
  
• Water pH
  
• Matching pH
  
• Rocks and pH
  
• Nitrates
  
• Phosphates
  
• Oxygen
  
• Water Hardness
  

Solving Water Problems

• Cloudy Water
  
• Green Water
  
• Yellow or Brown Water
  
• Oily Surface Slicks
  
• Foamy Water
  
• Elevated Water Temperature
  
• Amonia Poisoning
  
• Nitrite Poisoning
  
• Crashing pH
  
• High Iron