Caulpera: Seaweeds

The Good, The Bad & The Really Bad

Caulerpa is a genus of seaweeds in the family Caulerpaceae (among the green algae ). They are unusual because they consist of only one cell with many nuclei , making them among the biggest single cells in the world. There are 84 recognized species  A species in the Mediterranean can have a stolon more than 3 metres (9 ft) long, with up to 200 fronds.

I’ve personally encountered all of these species

Caulerpa Sertularioides

Caulerpa Racemosa

Caulerpa Racemosa var Clavifera

Caulerpa Taxifolia
Available at Seahorse
Use in Seahorse tank

Caulerpa Racemosa
Multibranch Form

Valonia Aegagropila

Caulerpa Lentillifera

Caulerpa Prolifera

Ventricaria Ventricosa

Bryopsis Algae

Bryopsis is a genus of marine algae, specifically of the Bryopsidaceae. It is frequently a pest in aquariums, where it is commonly referred to as hair algae  There are 55 species

This algae can be mistaken for hair algae as it begins to grow.  As it grows it starts to look more and more like a fern then hair algae.  As with the hair algae, your clean up crewwon’t touch this stuff once if grows very long.  Bryopsis will typically be found growing on your rocks and will be a shade of green in color.

The 2 most common species

Coralline Algae

Its a red algae in the order Corallinales. This is not a nuisance algae, but a algae that thrives and grows in good water conditions. It will grow on almost any surface in your tank (except the substrate). Once you start seeing Coralline Algae in your tank, you will know that your tank is starting to mature and your water quality is good.

They are characterized by a thallus that is hard because of calcareous deposits contained within the cell walls. The colors of these algae are most typically pink, or some other shade of red, but other species can be purple, yellow, blue, white or gray-green. Coralline algae play an important role in the ecology of coral reefs . Sea urchins , parrot fish ,limpets (mollusks), and chitons (mollusks), feed on coralline algae.

3 colors of Coralline
This algae usually dies when exposed to air especially during shipping. To introduce coralline it must come from an outside source. Only the center color seems to grow in aquariums.

NOTE The difference between Coralline algae above and Red Cyano bacteria AKA Red Slime algae below


A genus of green macroalgae. The algal body (thallus) is composed of calcified green segments. Calcium carbonate is deposited in its tissues, making it inedible to most herbivores.

As in other members of the order Bryopsidales, individual organisms are made up of single multi-nucleate cells. Whole meadows may consist of a single individual alga connected by fine threads running through the substrate.

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