In-Depth Guide to Fish Keeping: The Complete Beginner’s Guide
Introduction
Setting up a successful aquarium is both an art and a science. Fishkeeping is one of the most rewarding hobbies—it combines observation, creativity, and the calming, therapeutic benefits of caring for living creatures. However, this hobby requires preparation and understanding to ensure long-term success. Cutting corners or starting without the right knowledge can quickly turn a relaxing pastime into an infuriating and costly mistake.
Many beginners make the same error: they set up a tank, add fish, and within days or weeks the fish begin to die. These failures usually happen because advice was misleading, the process was rushed, or key details were overlooked. Missing these critical steps not only wastes money but also prevents you from experiencing the full joy and fascination of a thriving aquarium.
This guide will give you a comprehensive overview of aquarium basics, covering everything from tank choice and filtration to feeding, maintenance, and compatibility. At the end, I’ll also share my preferred tank style, a setup I find easy to maintain, cost-effective, and endlessly interesting.
Choosing the Right Aquarium
Choosing the right aquarium is the foundation of your success. There are many ways to acquire a tank: browsing online stores, visiting aquarium shops, looking for second-hand tanks, or having a custom tank built. Each option has its own advantages and considerations.
Tanks come in a wide variety of designs and glass types. For example:
Low-iron glass provides a crystal-clear view of your tank and its inhabitants.
Bowfront or curved tanks can be visually striking, but the curved structure makes them more prone to cracking.
Tank stands are just as important as the tank itself. They must distribute weight evenly; uneven weight can lead to cracks, leaks, flooding, and the loss of all your fish.
Second-hand tanks can be very reliable if checked carefully. Leak tests are essential, but older tanks that have been maintained well are often the most durable and trustworthy.
Tank size should satisfy both biological and behavioral needs. A 40-litre tank may be biologically sufficient for fast-swimming tetras, but it doesn’t allow them to express natural swimming behavior. Larger tanks give fish the freedom to shoal properly, explore, and exhibit fascinating, natural interactions that smaller tanks simply can’t support.
Lighting for Your Aquarium
Lighting is one of the most important aspects of a successful aquarium, particularly in planted tanks. Light not only helps plants photosynthesize and grow but also enhances the colors and natural behaviors of your fish. When setting up a planted tank, many hobbyists worry that lighting must be expensive, high-tech, or complicated—but this isn’t necessarily the case. In my experience, reliable, budget-friendly lights from sellers on eBay have worked perfectly for my setups. I’ve yet to have one fail, proving that you don’t always need to spend a fortune to achieve healthy plant growth and vibrant colors.
The type and intensity of light you need will depend on your plants and aquascaping goals. Low-light plants, such as Java fern or Anubias, will thrive under more moderate lighting, while high-light plants, such as carpeting species, may require brighter or more intense LED setups. The general goal is to provide enough light for photosynthesis without promoting excessive algae growth.
Key considerations for aquarium lighting:
Photoperiod: Most planted tanks do well with 8–10 hours of light per day. Too much light encourages algae, while too little slows plant growth.
Spectrum: Plants benefit from full-spectrum lights that include both red and blue wavelengths. Many modern LED lights provide a spectrum suitable for plants without requiring special bulbs.
Placement: Position lights evenly above the tank to prevent shadowing and ensure all plants receive adequate illumination.
Cost-effective options: Expensive fixtures aren’t always necessary. Budget LED lights can provide sufficient intensity and longevity if they cover the full tank and offer a balanced spectrum.
Lighting also influences fish behavior and coloration. Fish tend to display more natural and vibrant colors under the correct light spectrum, and heavily planted areas with moderate light offer shaded regions where shy or territorial species can feel secure.
In summary, lighting is crucial for both plant health and aesthetic appeal, but it doesn’t have to be prohibitively expensive. With careful placement, appropriate photoperiod, and a reliable LED, even budget setups can produce stunning results in a thriving planted tank.
Filtration and Water Flow
Filtration is the heart of a healthy aquarium, and it has three critical aspects: mechanical, chemical, and biological.
Mechanical filtration physically traps debris, uneaten food, and waste.
Chemical filtration removes dissolved compounds using media like activated carbon, which can remove tannins, odors, and medication residues, but long-term use may also strip trace elements from the water.
Biological filtration relies on beneficial bacteria that process ammonia into nitrite and then nitrate, keeping the water safe for fish.
Other filtration options include UV sterilizers, which reduce pathogens, algae spores, and free-floating bacteria. Even simple systems like sponge filters or air-driven bubblers contribute significantly to water health. The bubbles don’t directly dissolve oxygen; instead, they agitate the water surface, which improves gas exchange and increases oxygen saturation.
Different species have different water flow and oxygen requirements. For example:
Bettas prefer gentle movement and don’t require intense surface agitation since they can breathe atmospheric air.
Hillstream loaches require high flow, strong water movement, and well-oxygenated water.
Cold-water species generally need higher oxygen levels, as cooler water holds more oxygen, whereas warmer water holds less.
Temperature stability is critical. Sudden fluctuations can cause stress and disease. White spot (Ich) is a common temperature-related illness, but temperature control can also be used therapeutically in some cases. Raising the temperature slightly can kill certain parasites, though care must be taken, as some pathogens reproduce faster under heat.
Understanding the Nitrogen Cycle
The nitrogen cycle is the most critical biological process in a tank. Fish excrete ammonia, and uneaten food or decaying plants contribute as well. Beneficial bacteria convert ammonia to nitrite, which is still toxic, and then to nitrate, which is less harmful.
Ammonia (NH3/NH4+) – produced by fish and decomposing matter, highly toxic.
Nitrite (NO2-) – converted from ammonia by Nitrosomonas bacteria, still toxic to fish.
Nitrate (NO3-) – converted from nitrite by Nitrobacter bacteria, less toxic and can be absorbed by plants or removed with water changes.
Aquasoil can simplify cycling. When paired with live plants, aquasoil naturally produces small amounts of ammonia, which plants and bacteria use immediately. This jumpstarts bacterial colonies, allowing the biofilter to establish efficiently rather than waiting for bacteria to grow from nothing. This process supports healthier water conditions and reduces the risk of early fish deaths.
Substrate and Aquascaping
Substrate serves multiple purposes: anchoring plants, supporting biological filtration, and contributing to aesthetics. Aquasoil is nutrient-rich and excellent for planted tanks. Sand works well for bottom-dwellers, as debris stays on the surface and can be gently siphoned away. Gravel traps debris between stones and can be vacuumed without disturbing plants.
When it comes to aquascaping, the more natural, the better, but creativity is welcome. Driftwood, rocks, and decorations can help create a sense of territory for fish. I personally love adding a fake skull in a heavily planted scape—it blends natural beauty with a spooky, personal touch. Avoid painted or dyed rocks, as the pigments can degrade over time and leach toxins into your tank.
Your aquascaping should balance aesthetics with functionality. Dense plant coverage provides hiding spaces, reduces stress, and allows territorial fish to establish areas without conflict. At the same time, open areas encourage swimming and exploration.
Feeding Your Fish
Fish diets vary widely and must match species needs. Herbivorous fish require plant-based foods, while carnivorous or insectivorous species need protein-rich diets. Some species consume wood, biofilm, or algae. Feeding strategies depend on species and tank type. Single-species tanks like bettas or dwarf cichlids: feed roughly the size of the fish’s eye per meal. Community tanks require careful observation to ensure all fish have access to food. Overfeeding is a common issue, but the risks depend on filtration efficiency, tank size, and species.
Routine Maintenance
Even with low nitrate levels, water changes are necessary. Continuous top-ups without proper water changes can cause mineral and salt buildup, which standard tests may not detect. Advanced setups may rely on RO water top-ups, with periodic supplementation of minerals. Always monitor TDS, KH, and GH levels to ensure a healthy environment.
Maintenance requirements can vary depending on the type of fish you keep. For example, African cichlids are herbivorous with strong territorial tendencies, meaning they often uproot and eat plants and disturb substrate. Because scapes for these fish are usually limited to rocks and driftwood, and plants can’t be used to help absorb nutrients, waste builds up more quickly. Additionally, keeping these fish slightly overstocked can help mitigate aggression, but it also means more frequent water changes are necessary to maintain water quality. Other species, like many small community fish or shrimp-focused tanks, may require less maintenance if the tank is balanced and well-planted.
Routine maintenance should also include cleaning filters with tank water, removing algae, and inspecting plants and hardscape to ensure both aesthetics and function are maintained. Adjusting your maintenance schedule according to the species in your tank ensures a healthy, thriving aquarium environment and minimizes stress for your fish.
Fish Compatibility
Fish compatibility is nuanced. Semi-aggressive species like dwarf cichlids may be aggressive toward their own kind, but usually ignore schooling fish or bottom-dwellers. Densely planted, well-scaped tanks allow these fish to establish territories, reducing conflict. Territorial behaviors and hierarchies can form naturally, letting each fish claim an area while others avoid it. Exceptions exist, and personality plays a huge role. Beginners should avoid trying to house multiple semi-aggressive species together until they have experience and a carefully planned layout.
My Preferred Setup and Maintenance Routine
My preferred tank is a large, roughly 100-litre aquarium, heavily planted using aquasoil capped with washed play sand from Bunnings. I stock many small species rather than one large statement fish. After cycling, I introduce shrimp as both enrichment and a natural cleanup crew. Shrimplets serve as food for the fish in a controlled way, while adult shrimp help remove leftover food and plant debris.
For water changes, I use a Bunnings pong pump connected to a garden hose, allowing me to efficiently drain and refill the tank. Initially, I siphon debris manually until the pump system is in place. This method makes maintaining a large, heavily planted tank manageable and ensures both fish and plants thrive.
