Some people will tell you that freshwater tropical fish are easy to keep, and I suppose in comparison to saltwater they could have a point! But, easy or not, there are certain fish beginner aquarists should avoid. Here’s my Top 5 list of freshwater fish that should be avoided by beginners.

5. The Angelfish

Platinum Angelfish
Platinum Angelfish

Angelfish are often very attractive to beginners, they easily recognisable with their unusual shape and are a great centrepiece for your aquarium.

What the local fish store doesn’t tell you is that they need good water quality at all times, can become aggressive towards everything once they start spawning, require a low flow tank and are likely to have their fins nipped at by pretty much every other fish in your aquarium that has a slight nipping tendency.

On top of all of that, they can grow to be fairly large and require a tall and long aquarium to suit their needs.

4. The Plecostomus

Common Plecostomus

The armoured cat fish, commonly known as Pleco’s may seem like a great choice for the beginner aquarists as it will surely help keep their tanks clean, but they have a few issues.

New fish keeper want to watch their fish and enjoy them, Pleco’s are often very shy and will spend practically all day hiding as they are nocturnal animals. They can also grow to an enormous size of up to 24″, a size the average aquarists tank is just not suitable for.

Due to the their size and being omnivores, they often create more mess than they clean, so regular large water changes will be a must with this fish.

They have also been known to be territorial and develop a taste for the mucus coating that some species of fish have and will latch on to the fish to suck the mucus off.

3. The Golden Algae Eater

Golden Algae Eater
Golden Algae Eater

Don’t let the name fool you, these fish are omnivores and will eat both algae and meaty food. They are not the best algae eaters around.

Not only do they not do the job their name suggests they will, but they also grow to a massive size!

The bigger they get, the angrier they get. They seem to hate every single one of their tank mates and will make it their mission in life to annoy everyone in the tank, potentially even kill them. They are highly aggressive and should not be attempted by beginner aquarists.

2. The Bala Shark

Bala Shark
Bala Shark

I’m actually bit sad to add this one to the list, but due to their tendency to grow up and bully everything in your tank, they have to be listed here.

In the right (enormous) tank, with the right parameters these fish will thrive and they can do well in groups, but its often best to keep just one of them in the tank to keep any aggression to a minimum.

I say they need an enormous tank because they can grow to be HUGE and they grow quickly! You will end up having to sell your fish or buy a bigger tank. (I personally chose the latter of the two)

1. The Discus

Male Discus
The Discus – King of the aquarium

My favourite freshwater fish is the Discus. How can you not love this fish?!

The problem is, they are fussy! The slightest swing in parameters will send them into a downward spiral, often resulting the loss of your stock… not easy to swallow at a minimum of £35.00 per fish as a juvenile.

I have seen people pay hundreds of pounds for these fish, just to loose them all within a week of putting them in the tank.

They need big tanks with specific tank mates and decorations in order to thrive. As much as I love these fish, the time and dedication required to keep them happy is more than most beginners are prepared to put in to the hobby.


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