Red Gracilaria

Gracilaria parvispora

Also known as Red Ogo, Ogo, Gracilaria, Red feeding algae

SaltwaterMacroalgaeCuttings

Red Gracilaria (Gracilaria parvispora) — Coughdrop12 · CC BY-SA 4.0

Care at a glance

Light: Medium light
CO2: No CO₂ needed
Temperature: 72–81°F; 22–27°C
Max height: 7.9 in; 20 cm

Growth rate: Fast
Placement: Background
Type: Macroalgae
pH: 8.0–8.4
Spread: 7.9 in (20 cm)
Nutrient uptake: Water column
Growth region: Submersed
Difficulty: Easy
Family: Gracilariaceae
Origin: Tropical and subtropical seas; commercially cultured strains including Hawaiian ogo

Overview

Red Gracilaria is a dual-purpose macroalga, grown both for nutrient export and as premium food for herbivores. It is an easy, fast-growing choice for a reef tank.

Did you know

Red Gracilaria is the same ogo sold in poke shops and seaweed salads. That is why herbivorous reef fish find it irresistible as a fresh live green.

Caring for Red Gracilaria

Set Red Gracilaria in a refugium or the display, or let it tumble gently in medium flow. Keep it at 72 to 81°F (22 to 27°C) and pH 8 to 8.4. It is hardy over a wide range of salinities and often does well at a slightly lower specific gravity than a typical reef.

It wants medium light and no added CO2. Stronger light makes it grow faster and greener but lightens the red, while softer light keeps its prized deep red. It draws its nutrients from the water. High nitrate and phosphate actually slow it down, so it does best once a tank is reasonably clean.

It grows fast, so trim it often. Trimmed fronds are a favorite treat for tangs and other grazers. Healthy fronds that are cut or break off grow into new plants.

Good to know

Red Gracilaria, Gracilaria parvispora, is a red alga in the family Gracilariaceae. Its genus is harvested worldwide for agar. It grows as short, cartilaginous, cylindrical branches in a bushy burgundy clump.

In the wild

Red Gracilaria grows in tropical and subtropical seas, in warm coastal waters. It is cultivated for food across the Pacific, and commercially cultured strains include Hawaiian ogo.