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
Growth rate: Medium
Placement: Background
Type: Macroalgae
Temperature: 72–81°F (22–27°C)
pH: 8.0–8.4
Max height: 7.9 in (20 cm)
Spread: 7.9 in (20 cm)
Nutrient uptake: Water column
Growth region: Submersed
Difficulty: Easy
Origin: Tropical and subtropical seas; commercially cultured strains including Hawaiian ogo
Family: Gracilariaceae

Overview

A dual-purpose macro grown both for nutrient export and as premium herbivore food. Set it in a refugium or display or tumble it gently in medium flow under moderate light. It grows faster and greener under stronger light but keeps its prized deep red under softer light. High nitrate and phosphate actually slow it down, so it does best once a tank is reasonably clean. Trimmed fronds are a favorite treat for tangs and other grazers.

In the wild

A bushy red seaweed of warm coastal waters, cultivated for food across the Pacific. It grows as short, branching burgundy fronds and is hardy over a wide range of salinities, often doing well at slightly lower specific gravity than a typical reef.

Good to know

Gracilaria parvispora is a red alga in the family Gracilariaceae, the genus harvested worldwide for agar and eaten as ogo. Its cartilaginous, cylindrical branches hold their color best under moderate light; stronger light lightens the red while dimmer light deepens it. It spreads in the tank by fragmentation of healthy fronds.