Learn to Keep Fish - as Pets or in a Commercial Aquarium

Fish can be readily kept as pets both indoors and outdoors in temperate climates, or indoors in cooler regions. The types kept will depend on such things as their availability, cost, climate (if kept outdoors), equipment available, and local laws (e.g. the keeping of certain fish may be prohibited in some areas).

Lesson Structure

There are 10 lessons in this course:

1. Scope and Nature of Aquarium Management
2. The Water Ecosystem
3. Water Quality and Management
4. Equipment and System Design
5. What Species of Fish to Keep
6. Fish Health
7. Freshwater Tanks
8. Simple Saltwater Tanks
9. Aquarium Maintenance
10. Breeding Fish

Aims

• Select, establish and manage freshwater and marine aquariums of different sizes, incorporating suitable plant and animal species.
• Explore the purpose, applications and management of aquarium systems.
• Understand aquatic ecosystems and the relationships between water, plants, animals and environmental conditions.
• Assess and maintain water quality to support healthy aquatic environments.
• Identify appropriate equipment, technology and filtration systems for different aquarium applications.
• Choose compatible fish, aquatic animals and plant species for specific aquarium environments.
• Recognise common health issues affecting fish, aquatic animals and plants.
• Apply appropriate management and treatment strategies for aquarium health problems.
• Establish and maintain freshwater aquarium systems.
• Develop knowledge of marine aquarium setup and management requirements.
• Implement routine aquarium maintenance practices.
• Explore fish breeding techniques and the requirements for successful reproduction of different species.

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Choosing the Right Fish and Aquarium Setup

Selecting fish is an important first step in successful fish keeping. Different species have unique needs, and understanding these requirements helps ensure you create a safe, healthy and suitable environment for your fish.

Before choosing fish, consider factors such as:

Aquarium Location and Environment

Decide whether an indoor aquarium or outdoor pond is most suitable. Outdoor fish ponds may be affected by climate, predators such as birds and cats, and local safety regulations. Indoor aquariums require careful consideration of space, equipment and environmental conditions.

Water Temperature and Fish Requirements

Fish species have different temperature needs. Tropical fish generally require heated water, while cold-water species may not tolerate warmer conditions. Understanding these requirements helps you select compatible species and maintain stable water conditions.

Tank Size and Number of Fish

The size of your aquarium must match the number and type of fish you keep. Larger populations require more space, filtration, aeration and maintenance, so planning ahead is essential.

Fish Compatibility and Behaviour

Not all fish can live together peacefully. Some species are territorial, aggressive or predatory, while others have specific social requirements. Choosing compatible species helps reduce stress and promotes healthier fish.

Cost, Time and Ongoing Care

Successful fish keeping involves more than purchasing fish. Consider the costs of tanks, gravel, plants, decorations, filtration, heaters, aerators, food and water treatments. Regular maintenance, including feeding and water changes, is also essential.

Understanding Fish Growth

Many fish are sold when they are young and may grow significantly larger. Knowing the adult size, behaviour and care requirements of each species will help you provide an appropriate long-term environment. By understanding these factors, you can make informed decisions when selecting fish and designing an aquarium that supports animal health, wellbeing and a thriving aquatic ecosystem.

 

Types of Pet Fish

Pet fish are generally grouped into three main categories based on their water requirements and natural habitat:

• Cold-water fish – species that thrive in cooler temperatures and usually do not require a heated aquarium.
• Tropical fish – species that require warmer water conditions, often supported by aquarium heating systems.
• Marine fish – saltwater species that require specialised aquarium environments to replicate ocean conditions.

Cold Water

There are lots of different fish that may be kept in ponds or tanks without heating the water; though goldfish are by far the most popular. Goldfish prefer a water temperature around 22^oC and pH close to neutral, or slightly alkaline, but will tolerate lower temperatures.

For every 2 litres of water, you can keep up to 1cm in length of fish.  The most commonly kept freshwater fish are Goldfish. Goldfish come in various types, including: Comets, Fan Tails, Black Moors, Calico and Shubunkin.

Tropical

These are generally kept at around 25^oC. The water pH should be 6.8 to 7, and you should avoid using hard water.
For every 1 litres of water, you can keep up to 1cm in length of fish.
Common Tropical Fish include:

• Live Bearers - Guppies, Mollies, Swords, Platys
• Tetras - Neons, Harlequins, Head Lights, Tail Lights, Glow Lights
• Catfish - Corydoras, Plecostomus
• Rasboras - Harlequins, Scissor Tails
• Barbs - Tiger Barbs, Cherry Barbs, Rosy Barbs 
• Cichlids - Angel Fish, Discus, Firemouths
• Gouramis - Blue Gouramis, Gold Gouramis, Three Spot, Dwarf, Pearl, Moonlight

Marine

Marine fish can be more complicated to keep, and may require more expensive equipment.

Why do this course?

• Learn about caring for a range of fresh and salt water fish.
• Understand Cold Water, Tropical and Marine species habitat and requirements.
• Develop the knowledge and skills to set up and establish aquariums large and small.
• Identify different species of fish.
• Work in the Aquarium industry, or start your own business.

 

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