Fish For Beginner Aquarists To Avoid
What’s the best part of setting up a your new aquarium? Picking out your fish! And while there is a vast selection of fish to choose from, some are better choices than others. If you’ve never managed a marine aquarium before, you could find yourself struggling to meet the demands of some of these more difficult species.
Some fish are aggressive, require specialized diets, or need larger aquariums than most new hobbyists can provide. Choosing the wrong species too soon can lead to frustration, livestock loss, and even tank crashes.
To help you succeed, here’s a guide to fish beginner reef keepers should avoid — and why.
Mandarin Dragonets
Mandarins are among the most beautiful reef fish, but they require a constant supply of live copepods to survive. In new aquariums, pod populations are rarely large enough to sustain them, leading to slow starvation.
The only time we would recommend keeping a Mandarin is once your tank is mature (12+ months) and has an established refugium or regular copepod supplementation.
Moorish Idol
Iconic and striking, Moorish Idols are notoriously difficult to keep alive in captivity. They often refuse prepared foods, require large tanks, and are prone to stress-related illnesses.
The Longfin Bannerfish offers a similar appearance but is far more manageable for the beginner aquarist.
Clown Tang
Despite their beauty, Clown Tangs are extremely aggressive and need vast swimming space (600L+ tanks). They often outgrow beginner aquariums and can harass other fish to death.
In smaller tanks, these active fish can quickly become stressed and infect your aquarium with marine ich, if not quarantined beforehand.
Anthias
While stunning in groups, Anthias can be demanding. Many require multiple small feedings per day, which can overwhelm new hobbyists and destabilize water quality.
A beginner friendly option for Anthias are Lyretail Anthias. They are slightly hardier and may not require as many feedings in a day. They are still best left until you’re comfortable with regular feeding routines.
Sharks & Rays
They may seem fascinating, but sharks and rays require enormous aquariums, specialized diets, and pristine water conditions. Most beginners cannot provide the environment these animals need to thrive.
Copperband Butterflyfish
Copperband butterflyfish feed on coral polyps, making them unsuitable for reef tanks. They also have specialized feeding requirements, are extremely difficult to get feeding on prepared foods and are prone to stress.
When starting out, stick to hardy, reef safe fish that are well suited for smaller tanks and easier diets. Popular beginner choices include: Ocellaris or Percula Clownfish, Royal Grammas, Fire Gobies and Bangaii Cardinalfish.
By avoiding difficult or aggressive species early on, you’ll create a stable foundation for your reef and enjoy long term success.
