SDI Reef Fish Identification

The SDI Reef Fish Identification Course at OCD Divers teaches you how to recognize and identify a wide variety of reef fish species by their shapes, markings, behaviors, and habitat preferences. This course enhances your underwater experience by helping you understand what you are seeing and how different fish interact with the reef ecosystem. Training may be conducted in a local Texas lake or during OCD Divers dive trips, depending on the type of certification you choose.

This specialty may be completed as a non‑diving snorkeling certification or as a diving certification with two open water sessions.

What You’ll Learn

This course follows SDI standards and covers the essential knowledge needed to identify reef fish confidently:

• Form and function: How body shape, fins, coloration, and anatomy relate to behavior and habitat.
• Sex and gender roles: Benthic egg layers, live‑bearing species, and how life stages differ.
• Life stages: Larval, juvenile, and adult forms and how they change appearance.
• Reef habitats: How fish adapt to different reef zones and structures.
• Taxonomy: Major groups including sharks, rays, and teleosts.
• Reef fish behavior: Predators, planktivores, herbivores, cleaning symbiosis, mimicry, and social interactions.
• Observation techniques: Transects, passive observation, and how to record fish behavior.

Program Overview

The Reef Fish Identification Course includes two open water sessions (for diving certification) or two snorkeling sessions (for non‑diving certification). Each session includes general and specific observations, behavior recording, species comparison, and post‑session review. Sessions must take place at two different sites or at different times of day.

Prerequisites:

• For diving certification: SDI Open Water Scuba Diver or SDI Junior Open Water Diver.
• For non‑diving certification: SDI Snorkeler or equivalent.

Minimum age: 18, or 10 with parental consent.

Equipment needed: Snorkeling gear for the non‑diving certification or a complete scuba kit for the diving certification. A diver’s slate is required for all versions of the course.

Where Training Takes Place

Training may be conducted in a local Texas lake or during OCD Divers dive trips. Texas lakes provide excellent opportunities to practice observation techniques and identify freshwater species, while ocean trips allow divers to apply skills to tropical reef environments.

Required Gear

Divers must have a complete scuba kit for the diving version of the course, including mask, snorkel, fins, boots, BCD, regulator set, gauges or computer, exposure protection appropriate for conditions, surface signaling devices, and a cutting tool. Snorkelers must have standard snorkeling equipment. A slate is required for all participants.

Gear packages and rental options are available. Visit our continuing education gear options here: Continuing Education Diver Add On Options

What Comes Next

After completing the Reef Fish Identification Course, divers often continue with specialties such as Digital Underwater Photography, Shark Conservation Diver, or Navigation Diver. This specialty also counts toward the SDI Master Scuba Diver pathway.