Marine Algae in the Saltwater Fish Tank

At one time or another, virtually all saltwater fish tanks will have a marine algae problem. Below is a list of the most common kinds of algae, where they come from and how to get rid of them so you can continue to enjoy your crystal clear water!

Blue-Green Algae or Cynobacteria

Contrary to what the name implies, blue-green algae is actually a bacteria called Cyanobacteria. It is very easy to get and tough to eliminate. It feeds on nutrients found in the water and its spread can sometimes be seen hourly. They favor poor water conditions however they can survive in almost any water conditions.
Blue Green algae is caused by:
- deteriorating water conditions.
- overfeeding and overstocking of the aquarium
- Poor water flow/current
Solutions to blue-green algae / cyanobacteria:
- Make sure you have a protein skimmer and its working properly
- Weekley water changes.
- Adding an ozonizer - do not attempt if you have corals or invertebrates. this method should only be used by experts and must be closely monitored only as too much ozone could kill the inhabitants of the marine aquarium.
- UltraLife Red Slime Remover works very well.
- Reduce feeding and remove some fish if you have your tank overstocked. Remember that there should be about 1 inch of fish to every 5-7 gallons of water overstocking is a cause of this type of algae.
- Siphon out as much algae as you can.
- Add powerheads to increase the flow/current
- Check the phosphate levels - Rowa Phos works well to lower phosphate

Hair Algae

Unmistakable, this algae is green and looks like long hair, as the name suggests. Once you spot this pest, treat it right away or it may quickly overtake your tank! This type of marine algae is caused by:
- Phosphates, nitrates and sulphate which is commonly found in tap water. If you have been using tap water for your water changes, you are adding to the problem! Use only reverse-osmosis water with your saltwater fish tank.
Solutions to hair algae:
- Water change (with reverse osmosis water only!) this will immediately eliminate nitrates.
- Purchase a nit rage sponge which is placed in your filter and absorbs nitrate from the water.
- Siphon out as much algae as much as you can
- many fish species eat hair algae, visit your local fish store to see if they have any fish you can purchase. make sure to make note of the species you have in your tank currently to ensure their won't be any competitiveness between your fish.
- UV sterilizers will eliminate only free-floating algae

Red Brown Algae

Common in new aquariums as they cycle, this type of marine algae is caused by high nitrate levels in the water. In an established saltwater fish tank, this type of algae is signal of poor water quality. Solid dots of algae are actually microorganisms that grown in your tank. remove with algae scraper.
Causes of red of brown marine algae:
- high nitrates caused by new tank syndrome of poor water quality
Solutions:
- water changes with reverse osmosis water
- Purchase a nitrate sponge which is placed in your filter and absorbs nitrate from the water.
- UV sterilizers will eliminate only free-floating algae





Algae is natural so do not panic of you find it. Even though some types are caused by poor water quality, it serves as a reminder that aquarium maintenance in saltwater fish tanks if very important. Remember to do your water changes and you should be able to keep pests algae at bay.