Reef tank algae outbreaks will happen. In general, trying to lower phosphates and nitrates can be helpful. It won’t necessarily cure the problem once an algae has taken hold however. UV sterilizers may help with some algae types. Additionally, dosing magnesium or other additives can help with other algeas. Also, refugiums or Algae Turf Scrubbers can be helpful as a preventative solution and even controlling an outbreak if added.
Remember, while our enthusiasm for adding something new to our tanks can be compelling, be sure to quarantine. Consequently, not quarantining can lead to the problems you’ll see listed below.
Common Reef Tank Algae
Diatoms
Cause / Trigger / Ideal Conditions
- The recent addition of sand, rock, or plastic can trigger
Suggested Clean-Up Methods
- Wipe glass
- Blow rocks with a turkey baster
- Siphon sand
Cure
- Will starve itself out
Clean Up Crew
- Cerith Snails
- Nerite Snails
- Pods
Red Cyanobacteria
Cause / Trigger / Ideal Conditions
- High Phosphate Levels
- High Light Levels
Suggested Clean-Up Methods
- Wipe glass
- Lightly brush rock, corals, etc.
- Siphon sand
Cure
- Phosban/GFO
- Macroalgae Refugium
- Algae Scrubber
- Increase Live Rock
Clean Up Crew
- Cerith Snails
- Nerite Snails
- Blue Leg Crabs
- Emerald Crabs
Blue/Green Cyanobacteria
Cause / Trigger / Ideal Conditions
- High Phosphate/Nitrate Levels
- High Light Levels
- Low Flow
Suggested Clean-Up Methods
- Wipe glass
- Lightly brush rock, corals, etc.
- Siphon sand
Cure
- Phosban/GFO
- Macroalgae Refugium
- Algae Scrubber
- Increase Live Rock
Clean Up Crew
- Nerite Snails
- Cerith Snails
- Blue Leg Hermit
Calothryx Cyanobacteria
Cause / Trigger / Ideal Conditions
- High Phosphate Levels
Suggested Clean-Up Methods
- Scrub Rocks
Cure
- UV Sterilizer
- Peroxide Dosing
Clean Up Crew
- Nerite Snails
Lyngbya Cyanobacteria
Cause / Trigger / Ideal Conditions
- High Phosphate/Nitrate Levels
- High Light Levels
- Low Flow
Suggested Clean-Up Methods
- Lightly brush rock, corals, etc.
- Net Mass
Cure
- Phosban/GFO
- Macroalgae Refugium
- Algae Scrubber
- Increase Live Rock
Clean Up Crew
- Nerite Snails
- Cerith Snails
- Blue Leg Hermit
Green Film Algae
Cause / Trigger / Ideal Conditions
- The recent addition of sand, rock, or plastic can trigger
Suggested Clean-Up Methods
- Wipe glass
- Scrub Rocks
- Siphon sand
Cure
- Phosban/GFO
- Macroalgae Refugium
- Algae Scrubber
- Increase Live Rock
- Increase Flow
Clean Up Crew
- Cerith Snails
- Nerite Snails
- Turbo Snails
- Filter Feeders
- Amphipods
Green Hair Algae
Cause / Trigger / Ideal Conditions
- High Phosphate/Nitrate Levels
Suggested Clean-Up Methods
- Pull Out
- Net Sand
Cure
- Phosban/GFO
- Macroalgae Refugium
- Algae Scrubber
- Increase Live Rock
Clean Up Crew
- Turbo Snails
- Blue Leg Hermit
Bryopsis
Cause / Trigger / Ideal Conditions
- High Nutrient Levels
Suggested Clean-Up Methods
- Manually remove
- Remove rock first if possible
Cure
- Increase magnesium above 1400
- Dose Fluconazole 20mg/gallon
- Reduce lighting
Clean Up Crew
- None
Green Bubble Algae
Cause / Trigger / Ideal Conditions
- High Phosphate/Nitrate Levels
Suggested Clean-Up Methods
- Manually Remove
Cure
- Phosban/GFO
- Macroalgae Refugium
- Algae Scrubber
- Increase Live Rock
Clean Up Crew
- Naso Tang
- Rabbitfish
- Foxface
- Emerald Crab
Dinoflagellates
Cause / Trigger / Ideal Conditions
- Low nutrients
Suggested Clean-Up Methods
- Manually remove
- Some report raising water temp to 82ºF solved the problem
- raise pH to 8.4 or higher
Cure
- Phosban/GFO
- Macroalgae Refugium
- Algae Scrubber
- Increase Live Rock
Clean Up Crew
- None
Grape Culerpa
Cause / Trigger / Ideal Conditions
- Macroalgae used in refugium for phosphate control
- Can hitchhike into your tank
- DO NOT use in refugium
Suggested Clean-Up Methods
- Manually remove
- Be sure to remove all pieces
Cure
- Phosban/GFO
- Macroalgae Refugium
- Algae Scrubber
- Increase Live Rock
Clean Up Crew
- Tangs
- Rabbitfish
- Emerald Crab
Final Thoughts
Algae outbreaks are going to happen. Hopefully with good reef keeping practices and these tips they won’t turn into disasters requiring a complete tank breakdown.
Most of all, be sure to quarantine anything new you add into your aquarium. It’s a simple step that can prevent a major problem.
