Species that every beginner should avoid

Keeping and maintaining marine life can be a challenge for people who are new to the hobby. It can especially difficult when you have difficult to maintain species. After all, there are so many fish out there and so many choices – and if things weren’t confusing enough – many of the species that are commonly found in pet stores and other places aren’t easy to maintain.

Today’s blog is going to be about the species of fish that beginners should avoid putting into their tank until they’re ready. If you see a fish that you are interested in on this list, then maybe it’s something you’ll want to reconsider. Let’s jump right in!



Filefish comes from the same order as pufferfish. They’re not the worst choice on this list, but they’re certainly not a good one. The issue is that they’re a little destructive. They’ll frequently go after your corals when on an empty stomach – and have also been known to chase invertebrates like urchins around when in search of food.

You need to keep up a steady flow of food as they tend to like to graze – AND it needs to be both of the vegetable type and the meat type. They’re a great choice for experienced owners, but we recommend staying away if you’re a beginner.


In many cases, there are just some species that aren’t just best left to experienced tank owners – but better off left in the wild, period. That’s our take on eels – and more specifically – ribbon eels. The fact is – most end up dead in a few weeks of purchase and they don’t handle captivity well at all.

The biggest issue is their diet. They refuse feeders often and get easily stressed. They’ll often put themselves on stress patterns and well, they just waste away. They’re absolutely beautiful animals to have and trust us when we say we get the temptation, but you’re best off leaving them be. Especially if you’re a beginner.


Seahorses definitely fall into that ‘great in theory’ category, but almost never work out as expected. Again – the issue is a rather complicated pattern of care. They need to feed three times a day, be in a very friendly-to-seahorsies tank and the water needs to be kept meticulously. Sound like a lot? Well, because it is. Most beginners don’t want to put up with the maintenance and if you don’t, you’ll lose your seahorses. So we recommend that you just pass.


There’s a lot of lionfish out there – but we’re talking about your classic, definitive ‘lionfish,’ here. They are one of the most beautiful species you can own, but you’re going to need an awful lot of dedication to keep them going.

They have three qualities about them that will be a challenge: their size, their aggression levels and their spikes. They get big quick and like to eat anything that can fit into their mouth. They can even sting you. So – if you’re new to this whole fish tank thing – there are literally hundreds of other species who’d be a better choice.


Owning a fish tank is a wonderful experience. Just make sure that if you decide to get into it that you take things a step at a time. Good luck with your new aquarium! You’re going to love it!

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