Saltwater Aquarium Fish to Avoid

This article is aims to offer you advice regarding which fish do not fit well into the average saltwater aquarium. If you are a beginner we advise that you use this article as a guide to avoid problems and it may help you save money. Some fish look weird and wonderful and look like fun to keep, but the challenge can be too much for some and the last thing you want is to keep inappropriate fish in your tank.

  • Moray Eels - These fish look funky and are generally nocturnal. They spend most of their day inside small holes and will come out at night to feast on the rest of your fish! In the wild these fish can grow to up to 5 feet long!
  • Boxfish - Boxfish are so named because they are box-shaped. They can release a poison into the water and can also be a danger to their own species.
  • Seahorses - It requires a great deal of skill to keep seahorses and generally they are better kept on their own. The quality of the water needs to be of such high quality that this is best left to the expert.
  • Parrotfish - These can grow to a big size and take over your aquarium. Also they can damage any coral that you have in your tank.
  • Lionfish - Similar to the scorpionfish, lionfish are predators and will easily kill of the majority of fish in your tank.
  • Skates and Rays - Both of these species grow to a very large size and are a relation of the shark, so may eat most of your other expensive fish.
  • Stonefish - These fish have venomous glands near the base of their dorsal fin. The venom that they produce is fatal to humans and for this reason they can be difficult to keep. They are experts at disguising themselves as stones and rocks and when you put your hand in the tank... they strike!
© Loving Your Pet 2025. All rights reserved