Holy Grail Seaweeds: Are There Really Premium, Rare Macroalgae?

It is almost inevitable that people will pick “the pretty ones” out of the bunch. Many popular ornamental species/cultivars (koi, decorative maize, etc.) originated as farmed food species. We certainly may be seeing the same at this time with certain types of macroalgae in the marine aquarium hobby.

We now have long-finned clownfish. Already. It is not hard to imagine that in the coming years we could see a good many varieties of “domesticated” ornamental marine algae. These seaweeds will be cultivated (and perhaps even selectively bred) specifically for their aesthetic value. At least for now, we will have to be satisfied (and certainly should be) with the numerous forms (and even species) that have just reached the aquarium trade in more recent times.

Going glam

Many, if not most, aquarists initially acquire macroalgae as a means of reducing excess dissolved nutrients (thereby controlling nuisance algae). Accustomed to the generally modest growth rates of aquarium animals (e.g. corals and clams), some reef aquarists are astounded by the sometimes very rapid growth of macros such as Ulva and some Gracilaria. Perhaps some even used Caulerpa “back in the day” and just forgot how prolific this stuff can be.

There most definitely is something satisfying about such clear success and such instant gratification. And emboldening… Given the relative ease which he or she cultivated other macroalgae species, an aquarist could feel justifiably confident in trying newer, more exotic types.

“Exotic?” Really? Seaweed? Absolutely. It’s really about their desirability and their supply. As it is, many are in very low supply. This is for two reasons. First, growers tend to focus on the made-for-the-fuge “nutrient sponge” types because hey, that’s where the strongest demand has been. But another reason that ornamentals often get overlooked by producers is because they tend to be a little more difficult to grow and/or grow at considerably slower rates.

But we like pretty stuff, do we not? That is certainly so with aquarists. And, over time, demand for truly ornamental macroalgae has risen considerably. This has occurred along with an overall growing interest in marine botany. The result is the emergence of premium specimens in boutique stores. Now, curiously, very small pieces of select macro species are sometimes offered much like coral frags, meticulously mounted on plugs! And indeed, offered at select prices.

Three awesome and unusual macros to look out for

Perhaps you are interested in setting up a refugium, mainly for the purpose of cultivating ornamental species and creating a marine garden display tank. You might have had a planted refugium (full of utilitarian types such as Chaetomorpha) running for quite some time and are eager for a little more variety of color and form.

We here suggest a few rarities that can be obtained at AlgaeBarn. As the originators of the “clean” macroalgae for marine aquaria, you can be sure, first of all, that these products are highly unlikely to carry pests or diseases such as Aiptasia, Cryptocaryon (marine ich), etc. Also, considering the generous portion sizes offered, you can stock a refugium densely and beautifully without breaking the bank.

Now, we really mean “to look for” here. These species/varieties require more care during production, and are in high demand when they appear, so some types are of only limited availability. This is certainly the case with our three selections. But they do appear often and should definitely be looked at; get them while you can!

• • • Dragon’s tongue (Halymenia dilitata)

      Dragon’s tongue is prized by reef aquarists as an ornamental macroalga because of its bright red coloration and deeply furcated, flame-shaped fronds. It is pink to deep red in color. This beauty occurs throughout the Gulf of Mexico, the Caribbean, and the Tropical Atlantic Ocean. It favors rocky subtidal (usually reef-associated) environments. Unlike some other red algae, this species loves strong water currents. It grows either free-floating or attached to rocks. When attached, it can grow to heights of over 1.5 feet. Still, its growth rates are rather slow. Thus, it requires less frequent harvest than other macroalgae. It requires good water quality and good water movement for optimal health. It tolerates lower light conditions and therefore can flourish in shadier or deeper parts of the tank. Finally, it is extremely palatable and useful as a nutritious food for many herbivores.

    • Leafy sphere (Halymenia maculata)

      Leafy sphere macroalgae is beautiful enough for use right in the main tank, provided it doesn’t house large herbivores. It is pink to purple to deep red in color. It is distinguished from its cousins (e.g. Gracilaria) in its thick blades which are broader and more rigid. Halymenia maculata occurs across the Western Pacific and Indian Oceans in rocky, reef-associated, subtidal environments. Like H. dilitata, it favors areas of moderate to high water flow. It grows either attached to rock or free-floating. Because it grows slowly, it requires harvesting less frequently than some other macroalgae. It loves good water quality and strong water movement. It tolerates lower light levels. It makes a great food (when harvested from the refugium) for herbivores such as tangs, rabbitfish, angelfish, etc.

    • Thick Ogo (Gracilaria sp.)

      The thick red ogo Gracilaria plant is an exceptionally beautiful macroalgae. From bright red to burgundy in color and sporting thick, flashy fronds, it adds a dash of color and texture to any refugium or saltwater aquarium. Thick Ogo is somewhat faster growing than the above examples and is quite hardy under usual conditions. This makes it a bit of a showy compromise, as it is attractive but also fairly good for nutrient export. Like the above examples, in addition to its good looks, it serves as a great live food for your hungry herbivores.