How to Set Up Your First Aquarium - Beginner's Guide Australia 2026

Beautiful aquarium with tropical fish

Updated for 2026 | Reading time: 8 minutes

There's something incredibly calming about watching fish glide through a beautifully set-up aquarium. If you've been thinking about starting your first fish tank, you're in for a rewarding hobby. But getting it right from the start is crucial for your fish's health and your enjoyment.

This beginner's guide will walk you through every step of setting up your first aquarium in Australia, from choosing equipment to adding your first fish.

Step 1: Choose Your Tank Size

Here's a counterintuitive tip: bigger is actually easier for beginners. Larger tanks are more forgiving because the bigger volume of water is more stable — temperature fluctuations are smaller, and waste is more diluted.

Recommended starter sizes:

  • 60-80 litres — Great entry point, manageable size, plenty of fish options
  • 100-120 litres — Ideal if you have the space, very stable water parameters
  • 20-40 litres — Suitable for a Betta or small nano fish, but requires more attention

Avoid: Bowls and very small tanks (under 15 litres). Despite what movies show, goldfish bowls are cruel and make fish keeping extremely difficult.

Step 2: Essential Equipment

Here's what you need to get started:

Filter

The most important piece of equipment. Your filter houses beneficial bacteria that convert toxic ammonia (from fish waste) into less harmful substances. Without it, your fish will get sick.

Types: Hang-on-back (HOB) filters are great for beginners. Internal filters work well for smaller tanks. Canister filters are best for larger setups.

Heater

Most tropical fish need water between 24-28°C. Australian homes can get cold in winter and hot in summer, so a reliable heater with a thermostat is essential.

Rule of thumb: 1 watt per litre of water (e.g., 100W heater for a 100L tank).

Thermometer

Don't rely solely on the heater's dial. A separate thermometer lets you verify the actual water temperature.

Lighting

LED lights are the standard in 2026 — they're energy-efficient, adjustable, and many come with day/night timers. If you plan to grow live plants, make sure the light is suitable for plant growth.

Substrate

The material at the bottom of your tank. Options include:

  • Gravel — Classic, easy to clean, comes in many colours
  • Sand — Natural look, required for some bottom-dwelling fish (like Corydoras)
  • Planted substrate — Nutrient-rich, ideal if you want live plants

Water Conditioner

Australian tap water contains chlorine and chloramine, which are toxic to fish. A water conditioner neutralises these chemicals instantly. You'll use this every time you add tap water to the tank.

Test Kit

A liquid test kit for ammonia, nitrite, nitrate, and pH is essential, especially during the cycling phase. API Master Test Kit is the gold standard.

Step 3: Set Up Your Tank

  1. Choose a location — Away from direct sunlight (causes algae), near a power outlet, on a sturdy surface that can handle the weight (water is heavy — 1 litre = 1 kg!)
  2. Rinse everything — Rinse gravel/sand, decorations, and the tank with plain water (never soap!)
  3. Add substrate — 3-5cm depth is ideal for most setups
  4. Place decorations — Rocks, driftwood, and plants (real or artificial). Create hiding spots for fish.
  5. Fill with water — Place a plate on the substrate and pour water onto it to avoid disturbing the layout
  6. Install equipment — Filter, heater, thermometer, light
  7. Add water conditioner — Follow the dosage on the bottle
  8. Turn everything on — Let it run for 24 hours to check everything works

Step 4: Cycle Your Tank (The Most Important Step!)

This is where most beginners go wrong. The nitrogen cycle is the process of establishing beneficial bacteria in your filter that convert toxic waste products into safer compounds.

Without cycling, your fish will suffer from "New Tank Syndrome" — ammonia poisoning that can be fatal.

How to Fishless Cycle:

  1. Set up tank with filter running (no fish yet!)
  2. Add an ammonia source — pure ammonia (from hardware stores, ensure no surfactants) or fish food
  3. Dose ammonia to 2-4 ppm
  4. Test water every 2-3 days
  5. After 1-2 weeks, nitrites will appear (bacteria are growing!)
  6. After 4-6 weeks, ammonia and nitrites should both read 0, and nitrates will be present
  7. Do a large water change (50-70%) and your tank is ready for fish!

Quick-start option: Using established filter media or a bacterial supplement can speed this up to 1-2 weeks.

Step 5: Choose Your First Fish

Now the fun part! But choose wisely — not all fish are suitable for beginners or for every tank size.

Best Beginner Fish in Australia:

  • Neon Tetras — Peaceful, colourful, schooling fish. Keep in groups of 6+
  • Corydoras Catfish — Adorable bottom-dwellers, great cleanup crew. Keep in groups of 4+
  • Bristlenose Pleco — Excellent algae eater, stays small (unlike Common Plecos!)
  • Betta Fish — Stunning colours, great personality. Keep one male alone or with peaceful tank mates
  • Guppies — Hardy, colourful, easy to breed (sometimes too easy!)
  • Cherry Barbs — Peaceful, active, beautiful red colour
  • White Cloud Mountain Minnows — Hardy, don't need a heater in Australian climates

Stocking Rules:

  • Add fish gradually — 2-3 at a time, with 1-2 weeks between additions
  • Research compatibility — not all fish get along
  • Don't overstock — the old "1cm of fish per litre" rule is a rough guide, but research each species

Step 6: Ongoing Maintenance

Once your tank is set up and stocked, maintenance is surprisingly easy:

Weekly:

  • 20-30% water change (vacuum the gravel while you're at it)
  • Test water parameters (especially in the first 3 months)
  • Remove dead plant matter or uneaten food

Monthly:

  • Clean filter media in old tank water (never tap water — it kills beneficial bacteria)
  • Clean algae from glass
  • Trim plants if needed

Common Beginner Mistakes

  1. Not cycling the tank — The #1 cause of fish deaths in new tanks
  2. Overfeeding — Feed only what fish can eat in 2-3 minutes, once or twice daily
  3. Overstocking — More fish = more waste = more problems
  4. Cleaning too much — You want beneficial bacteria! Don't scrub everything spotless
  5. Buying fish on impulse — Always research before purchasing

Estimated Startup Costs (Australia)

Item Estimated Cost (AUD)
Tank (60-80L) $60-150
Filter $30-80
Heater $20-50
LED Light $25-60
Substrate + Decorations $30-60
Water Conditioner + Test Kit $30-50
First Fish $20-50
Total Estimate $215-500

Shop Aquarium Supplies at DeservePetGo

Getting into fish keeping? DeservePetGo stocks a growing range of aquarium supplies, decorations, and accessories to help you set up the perfect underwater world. We're an Australian-owned store and all orders ship free across Australia.

Browse Our Aquarium Collection

Happy fish keeping, mate! It's a brilliant hobby once you get the hang of it, and there's nothing quite like watching your own little underwater ecosystem thrive.