All aquariums have some form of algae. It’s normal and can even be beneficial. But algae overgrowth can harm your fish and plants. Understand the conditions that cause algae to grow and you will keep a healthy tank that is crystal clear year round.
What causes algae to grow?
- Leaving the aquarium in direct sunlight
- Overfeeding the fish
- Using water with high nutrients
- Leaving lights on too long
Keep in mind the three basic necessities for algae growth: water, sunlight and nutrients. Too much of any of these items can cause algae overgrowth. How?
Reducing algae growth
- Limit lighting – Avoid direct sunlight altogether and limit artificial lighting to about eight hours a day.
- Check your water and change it regularly – Partial water changes will help control nitrates and phosphates and in turn, algae. Also, test your source of new water for nutrients and use filter medias as well.
- Use live plants – One way to combat algae is to use live plants, which compete for the same nutrients that feed algae. If you include plants, use full-spectrum plant bulbs, which are good for about one year.
- Keep algae-eating fish – The Siamese Flying Fox, Otocinclus or Plecostomus will help keep algae levels low.
- Don’t overfeed – Overfeeding is common. One way to check is to watch your fish eat. If they don’t eat all of the food you give them in five minutes, you’re overfeeding. Remove uneaten food, which increase phosphate levels as well.
Using these tips will help you maintain healthy fish and an aquarium with little algae growth.
For filter media, aquarium supplies and more, visit your local Pet Supermarket or PetSupermarket.com.


