*Bryopsis plumosa Photo Courtesy of SaltCorner.com
Ok, so who hasn’t had some form of hair algae in their tanks? It’s a thin, fluffy and stringy algae that will grow fast, block out light to corals, and will become one of the most frustrating plants that you will ever have to deal with.
There are many different types and species of algae that get swept under the umbrella term “hair” algae. There’s Derbesia sp., Bryopsis sp., and Enteromorpha sp., to name just a few. By analyzing photographs and samples taken from people’s tanks, I notice most people the most problems with either Bryopsis or Derbesia.
*Derbesia marina Photo Courtesy of SaltCorner.com
The reason that hair algae is so difficult to control is that it grows unbelievably fast, can pop up anywhere in the tank, very few organisms will eat it, and typical nutrient control can barely keep it at bay. But there are methods of removal.
While typical nutrient reduction like water changes and protein skimmers won’t keep hair algae from popping up by themselves, a combination of methods can. If you combine aggressive water changes and protein skimming (frequently clean inside and out by the way) with the use of a phosphate absorber, carbon, and some other product like ZEOvit or Prodibio for further nutrient reduction, then the hair algae can be eliminated, or at least slowed down.
*Photo Courtesy of Aquarium Specialty
ZEOvit is a spectacular set of products that will reduce your nutrients to “ultra-low” status by utilizing bacteria for the filtration. Prodibio, sugar dosng, and vodka dosing all do similar things in that they help reduce nutrients via bacteria.
*Photo Courtesy of Aquarium Specialty
Most fish and invertebrates won’t really touch hair algea, but there are some that will. My personal fish of choice is the rabbitfish or the foxface. They are unbelievable algae hogs and will mow down most, if not all types of algae. I’ve seen them eat hair algae, bubble algae, and pretty much all algae that I had in my personal tanks. But sometimes they nip at zoanthids, so let’s look at other choices. Other tangs have been known to eat hair algae, but none are as consistent as the rabbitfish.
*Photo provided by the author
Some snails will eat hair algae. The jumbo Mexican turbo snails are voracious algae eaters. I have seen them eat a lot of different types of algae, especially hair algae. However, these snails get huge and will knock over coral frags, dislodge rocks, and can even cause rock slides if the foundation is too loose.
Sea hares are another invert that will mow down hair algae. They are essentially large, shell-less snails that do nothing but eat. Hair algae is one of their favorites, but I’ve seen some pass it right up. Not to mention, sea hares are very sensitive and do not ship well. Lettuce nudibranchs are also known to eat hair algae, but they stay smaller and are just as sensitive as sea hares.
Believe it or not, high magnesium levels are probably the most surefire way to rid yourself of hair algae. A normal reef tank has magnesium usually around 1250-1350 mg/L. If you have hair algae though, you can increase it to 1600 mg/L or more and the hair algae will whither and die. The livestock of the aquarium should remain unaffected, but keep an eye on calcium and alkalinity as they all balance each other out.
So, to rid yourself of hair algae, the best thing to do is reduce your nutrients (nitrates and phosphates), add more inverts to your cleanup crew, get a rabbitfish or a type of tang, increase your magnesium, and manually remove excess algae. It’s a lot of work, but it will certainly pay off. That stuff will get way out of hand if you don’t do something about it.
Aquarium Specialty – ZEOvit
Aquarium Specialty – Prodibio
Live Aquaria – Sea Hare
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