You are here:About>Home & Garden>Freshwater Aquariums> Problem Solving> Algae> Green Water
About.comFreshwater Aquariums
Other Types of Algae

BeardBlue-GreenBrown

Other Types of Algae

Gravel SlimeSpot

Green Water

From Shirlie Sharpe,
Your Guide to Freshwater Aquariums.
FREE Newsletter. Sign Up Now!
Other Names: Algae bloom
Color: Green tinted water
Appearance: The water itself turns green. In severe cases the water may be so green that the fish are not visible.
Cause:
  • Suspended microscopic algae
  • Excess light, especially direct sunlight
  • Too many fish
  • Excess nutrients
  • Excess wastes

    Green water is usually due to either a significant excess of light (particularly direct sunlight), or a major water quality problem. Although it may look terrible, it is not toxic to fish.
  • Cure:
  • Blocking out light completely
  • Diatomic or micron filtration
  • Introduce daphnia to the tank

    Water changes will reduce green water temporarily, but will not eliminate it. Completely blocking out all light for three days or more is very effective. The use of a diatomic filter will remove the suspended algae. If daphnia are available, they will quickly eat the microscopic algae, then in turn be eaten by the fish.
  • Note: Water aggregators that profess to clump suspended algae and remove it are not effective against green water.
    Prevention:
  • Regular water changes
  • Regular aquarium cleaning
  • Use of UV Filter
  • Avoid direct sunlight on tank
  • Avoid overfeeding fish
  • Do not overstock the tank

    As with any algae, keeping the tank clean and performing regular water changes is one of the best preventative measures. Prompt attention to sudden algae growth will prevent more serious problems
  •  All Topics | Email Article | Print this Page | |
    Advertising Info | News & Events | Work at About | SiteMap | Reprints | HelpOur Story | Be a Guide
    User Agreement | Ethics Policy | Patent Info. | Privacy Policy©2008 About, Inc., A part of The New York Times Company. All rights reserved.