Saltwater aquariums can be so diverse because of all the different varieties of marine life that you can add to it. One of the most popular types are schooling fish. These fish that swim together can add a beautiful touch to a large marine tank. It can be mesmerizing watching a group of fish swim in unison through the water. It can be even more pleasing to watch a group of coloful fish glide in and out of rocks and corals.
Having a group of fish swim through a saltwater aquarium as they were a single organism is facinating to watch. There are so many species of saltwater fish that you can put in your tank, and it is important to understand which type of fish like to school together. We will take a look at the best schooling fish for saltwater aquariums.
In your aquarium, blue-green chromis, anthias, dartfish, and cardinals are the best choices for schooling fish. If you are looking to add groups and movement to your tank, then you can get a few species that stay together. This will add a new dynamic to your saltwater tank.
What Exactly Are Schooling Saltwater Fish?
Schooling fish are species of fish that group together as mature adults. This happens in their natural habitat in the ocean and sometimes in home aquariums. If you spend any time watching fish, it can be easy to spot the schoolers. These fish will cluster in groups, and they will swim in the same direction almost in unison.
Fish school together for several reasons like protection, safety, efficiency, and feeding. These behaviors help the fish survive in the ocean, but usually these behaviors are not needed in a hobby size aquarium.
When it comes to schooling fish for saltwater aquariums, you will be limited on the species that you can have based on the size of your tank. While there are many different marine fish that school in the ocean, most of them will be too large or can’t adapt to home aquariums. Most fish for your aquarium will only be a few inches.
Using the formal definition of schooling, the odds of you having saltwater fish that actually do this are pretty rare. You likely won’t have the size needed, and most fish considered in this group won’t actually school. What you will see is actually called shoaling. This is the term used when fish congregate and stay near each other.
The term shoaling is actually more accurate to describe fish that hang out together in home tanks.
Best Schooling Fish For Saltwater Tanks
Anthias come in many different specimens, and it is important to not mix them. You should only keep one specimen in your tank for best results. There is nothing to say that you can’t mix species. You can if you want, and some reefers have had success doing this. But overall, you will do better with just one type. Some common types of Anthias are Lyretails, Dispar, Carberryi, and Ignitus. Its a good idea to get a couple more than you are planning because 1 or 2 may die off during quarantine, unfortunately.
You will need a minimum of 120 gallons to keep Anthias, but they will do better in larger aquariums. You could keep one in a 75 gallon tank, but we are looking for schooling fish here. You can get one male and several females for your group.
2. Blue Green Chromis
The Blue-Green Chromis (Chromis viridis) is a great schooling fish. The main draw to these fish is their ease of care and low price point. You can usually get these for around $10 or under, and for saltwater fish, that is a great price point. This species is usually widely available at your local fish store as well as online.
At a minimum, you should have no less than 3 of these in your tank, but they will do better in a group of at least 6. The fish will be less stressed in larger groups, and they will be healthier. They will tend to fight amongst themselves more if you keep less than 6 of them. With chromis, the more the merrier.
These fish like to swim together in the upper part of the tank, and they like to swim so its best to keep them in a longer tank. We recommend at least 3. They like to hide in the rocks sometimes especially at night, so make sure you have plenty of hiding places for them.
When it comes to feeding, these Chromis are aggressive eaters, and they are usually first in line when the food hits the water. This can make these fish more desirable because you can’t beat a school of Chromis feeding all at once. Chromis are great fish, but they seem to have higher death rates than a lot of other common aquarium fish.
A school of chromis can kill each other off over time. That does not happen 100% of the time, but it often does. However, a group can lasts for many years before doing this.
3. Longspine Cardinalfish
The Longspine Cardinalfish (Zoramia leptacantha) can shoal or “school” together. These fish are timid, and you will need some good hiding places for them as well. These group together well, and their only downside is their lack of brilliant colors. These saltwater aquarium fish are mostly translucent with some iridescent blue and yellow markings.
The minimum group size for Longspine Cardinalfish is 4, but if you can get closer to 10, they will do better. This will reduce their stress, and it will help with their overall health. Fish like to group together for safety and protection. If they don’t feel safe in a small space, they may feel stressed too much. If you keep only a few, you may find them to stay hidden a lot, and this will reduce the amount they feed.
4. Zebra Dartfish
Zebra Dartfish (Ptereleotris zebra) are great beginner fish that will shoal. There are many advantages to these marine fish, and some things you need to keep in mind as well. These are timid and peaceful fish, and they do not do well in tanks with aggressive fish. They are active, and they will dart in and out of your live rock structures. Live rock is important for many reasons, and these fish will use them as their playground as they move in and out of them. They are great feeders, and they make a wonderful addition to any tank.
Dartfish need to be at least paired in your tank, but they will do better with at least 5. While they won’t school in the traditional sense, they will shoal together as a group, and they are fascinating to watch.
These marine fish are easy to care for, and they are not too costly. The adult generally gets to around 4 inches, and they do best when introduced to your tank as a group instead of individually. It’s also a good idea to get a cover for your aquarium if you don’t have one. This species of fish are known to be jumpers.
5. Mono Argentus (Fingerfish)
The Fingerfish (Monodactylus argenteus) do a great job of shoaling, but one thing to keep in mind is how big they get once mature. A mature fingerfish can get up to 10 inches, and if you have a group of them, that is something to consider. We would not recommend you getting these unless you have at least a 120 gallon tank.
These are more advanced fish, so we do not recommend that you get these if you are new to the saltwater tank hobby. These fish can start out in freshwater when they are younger, but they will need to be moved to brackish water once they start to get mature. They do a great job of shoaling and are beautiful to watch in groups. These fish are not commonly seen in hobby aquariums.
Useful Information To Consider
Some important information to consider when adding fish that school or shoal is understanding each species.
- How big does it get?
- How long until the fish is mature?
- How many do I need?
- Do I have to add them all at once?
Fish that school together usually do best when they are added at the same time to your tank. You can still add more later, or you may have one that dies and you want to replace it. Sometimes the new fish will do well, and others may isolate or even get attacked.
It is important to understand the limitations of your saltwater tank, and when you are adding groups of 5 or more fish, it is even more important. You need to understand how big the fish are going to get relative to the size they are when you acquire them. No matter what size your tank is, it will have a limit on how much it can hold, and it is also limited by your equipment such as a protein skimmer.
Some fish that shoal together do better with certain numbers. Having one dartfish is not going to be the best for the health of that fish, so you need to make sure you ask your LFS what is the best number to get, and you will be limited by what you already have and how big your aquarium is.
Saltwater fish that are schooling are great additions to any large tank, and they can add depth and character to the environment. Whether you want to call it shoaling or schooling, either way, these fish are great to have.