Starting your first aquarium is exciting but it can also be overwhelming. The good news? Most beginner mistakes are easy to avoid with the right advice.

At Newtown Aquarium, we're here to help you build a healthy, thriving aquarium from day one. Whether you're buying your first fish or setting up a brand-new tank, our beginner-friendly collection has been selected because they're hardy, peaceful, and well suited to new fish keepers.

Mistake 1: Adding Fish to An Uncycled Tank

One of the biggest mistakes new fish keepers make is adding fish to a brand-new aquarium.

A new tank hasn't developed the beneficial bacteria needed to break down harmful waste. Without these bacteria, toxic ammonia can quickly build up and put your fish at risk.

How to avoid it:
Always cycle your aquarium before adding fish. Not sure if your tank is ready? Our team can help you get started.

See Water Conditioner

Mistake 2: Overfeeding Your Fish

It's tempting to feed your fish every time they look hungry - but overfeeding is one of the quickest ways to create poor water quality.

Uneaten food breaks down into waste, increasing ammonia levels and encouraging algae growth.

How to avoid it:
Feed only what your fish can eat in 1–2 minutes, once or twice a day. Less is often more.

Mistake 3: Choosing the Wrong Tank Size

Many fish are sold small but grow much larger than people expect.

Keeping fish in a tank that's too small can lead to stress, poor water quality, stunted growth and a shorter lifespan.

How to avoid it:
Research the adult size of your fish before purchasing, and choose an aquarium that gives them plenty of room to thrive. If you're unsure, we're always happy to recommend the right tank for your chosen species.

See Available Tanks

Beginner Friendly Species

1 25
View all

AFTER SOMETHING ELSE?

Explore our complete fish room selection; from rare and unusual species to classic fish species, thriving plants, quality inverterbrates plus premium aquarium equipment and nutritious food for thriving tanks.

Shop All Fish

Fishkeeping FAQ's

What is the best fish for beginners?

Species like Corydoras, Harlequin Rasboras, Cardinal Tetras and Bristlenose Plecos are all excellent choices for first-time fish keepers.

How long should I cycle my aquarium?

Most aquariums take between 4–6 weeks to establish the beneficial bacteria needed to safely support fish.

You can test the water with a test kit or visit us in store to see if your aquarium is ready for fish.

Do I need a filter?

Yes. A quality filter is one of the most important pieces of equipment in any healthy aquarium. It keeps the water clean and provides a home for beneficial bacteria.

How often should I change the water?

Most freshwater aquariums benefit from a 20–30% water change every week, depending on stocking levels and filtration.

Can I add all my fish at once?

It's usually best to add fish gradually, giving your aquarium time to adjust to the increasing biological load.

Need Help Getting Started?

Whether you're setting up your very first aquarium or looking for the right fish to suit your tank, our experienced team is here to help.

Visit us in-store, shop online, or get in touch, we'll help you build an aquarium that thrives.

66A Princes Hwy, St Peters NSW 2044

Phone:(02) 9519 3631

See our Beginner Fishkeeping Guides

View all
1 3
View all