STOCKING SALT WATER REEF TANKS

Written by Katherine Barrington Updated May 01, 2014
Learn how to select the right quantity and combination of fish for your reef aquarium.
Have you ever been snorkeling in the ocean or seen a thriving saltwater tank at your local zoo or aquarium? There is just something about a reef environment that seems so vibrant and alive. If you want to experience this beauty every day, consider starting your own reef tank at home. A saltwater/reef aquarium is an oceanic microcosm in your home. It needs to be ecologically balanced in order to retain its natural beauty. Too many fish, incompatible fish and a variety of other factors can ruin the stability of your tank's eco-system. In this article, we offer some guidance on correctly stocking your reef aquarium.
 
How Many Fish and Corals?
 
Achieving perfect stocking levels is not an exact science where saltwater/reef aquariums are concerned, but you can use a rule of thumb calculation to form an idea of how many fish and corals your tank should theoretically be able to accommodate. It is important to differentiate between smaller and larger species when considering how many fish to keep in your tank. Larger species occupy more space, have greater appetites and generate more waste. For this reason, the rules of thumb between small bodied and large bodied fish differ somewhat:
  • For small to medium fish, the rule is 2" of fish for every 10 gallons of tank capacity.
  • For medium to large bodied fish, the rule is 1" of fish for every 10 gallons of tank capacity.



Using the rules of thumb outlined above, this means that an 80 gallon tank can theoretically be stocked with either 16" of small fish or 8" of large fish. This rule of thumb is not the only deciding factor, though. The number of fish that can be accommodated in real terms is influenced by a variety of factors, such as:
  • the effectiveness of your filtration system;
  • the amount of invertebrates / corals that are present in the aquarium;
  • whether the aquarium is well established;
  • the actual volume of the tank once you have added aquarium equipment, rocks, sand, plants, ornaments and so forth to it.

Always base your rule of thumb calculations on the adult size of the fish, not on the juvenile size (which is how many fish are sold). If you will be introducing juveniles, make a point of finding out how big they become. If you are introducing mature fish, measure the fish from the base of its tail to its head. You never include the tail when measuring. Corals are a little different in that you can control the size of most corals. It is a good idea to decide beforehand how big you will allow them to grow.

Other Fish Factors

When stocking your reef tank, the size of your fish and the number of fish you choose are the most important factors to consider. These are not the only things you should think about, however. Other factors you need to consider in stocking your reef tank include behavioral compatibility and habitat compatibility.

Behavioral Compatibility -
All fish are predators to a greater or a lesser degree, and any fish - regardless of species - will be assertive or aggressive when it perceives the need to protect its territory, itself or its mate.

Here are a few of the factors worth considering when planning which fish to stock:

  • Highly predatory fish such as the Lionfish and Moray Eels should be kept in a separate tank from smaller fish. They are natural hunters and will cause devastation if you place them in the same tank as smaller fish.
  • New fish that are introduced into a settled aquarium community will usually be at the receiving end of aggressive territorial behavior, no matter what the species or type of fish. These disputes are natural and once the territories are re-established, the fish normally settle down.
  • It is important to have only one pair of any mated species of fish. All mated species, including Boxfish, Angelfish, Clownfish and Butterflyfish feel threatened when the same gender of their species is introduced to the tank and will attack as a result. If unavoidable, make sure that there is ample space and sufficient 'hiding places' for the new fish.

There are a few things you can do to minimize aggression. The first is space, space and more space. Secondly, go for diversity. An Angelfish is less likely to have a run-in with a Clownfish than with another Angelfish. The third is not to mix the littlies with the really large ones. All fish are predatory to some extent. This means that a small fish will become food if it can fit into the mouth of a bigger fish.

Habitat Compatibility - Compatibility does not only relate to the ability of fish to peacefully co-exist. It also relates to the similarity between fish in as far as their feeding, lighting and habitat requirements are concerned. Though two species of fish may both live in coral reefs, they may come from completely different oceans. Thus, these two species may be adapted to different levels of water chemistry. To ensure that your fish get along and thrive in your reef tank, you need to cater the conditions in the tank to the needs of your fish – this is easiest to do if all of the fish in your tank have similar needs. If your aquarium will contain corals, make sure that there is synergy between the fish and the corals' requirements as well.


Some Coral Factors

Because they are living creatures, corals have some compatibility and habitat considerations too. Here are a few factors you may want to make a note of during the planning phase of your saltwater / reef tank:
  • Compatibility - Check the compatibility of the corals you wish to use, both with one other and with the fish you intend introducing. For example, if part of your plan is to introduce anemone to give safe haven to your clownfish, do bear in mind that anemone eat certain other species of fish as well as shrimps.
  • Space - Offer each coral sufficient space within which to thrive. Like any other sea creature, coral will become aggressive if competition is perceived. When introducing soft coral, leave a clear space of approximately 3" around it. Hard coral, on the other hand, will require at least 6" of clear space around it.
  • Tip over potential - use epoxy to keep unattached coral in place when you first introduce these, otherwise it may tip over onto a neighboring coral, burn and die.
  • Lighting - this plays an important part in photosynthesis. Different corals have different lighting requirements which should be thoroughly researched. To achieve optimum beauty, it is better to select corals with compatible lighting needs.
  • Current - corals rely on the water movement around them to help keep them clean. Also bear in mind that different corals have different current requirements. Powerheads or a similar source of water movement should be installed to create current.

These factors, together with placement, will be the difference between success and failure.

Introducing Live Stock

Bear in mind that the corals should only be introduced to your saltwater aquarium after the live rock has cured completely and the aquarium is set up with all other equipment and filtration systems running smoothly. Give the tank at least 2 weeks to run without fish so that it can “cycle” – this refers to the establishment of the nitrogen cycle in your tank. During these first few weeks your tank will become colonized with beneficial bacteria that will help to break down waste and convert harmful toxins into less harmful substances. If you introduce your fish before the tank has cycled, they may overload the tank which could result in reduced water quality and toxic ammonia levels.

When you then start adding fish to your tank, resist the temptation of introducing more than two fish every two weeks. Your tank will need this time to adjust to the additional biological load. It is also best to add the hardiest fish first and to save the most sensitive species for last. When you do introduce your fish, do so slowly – float the bag containing your fish in the tank and add small amounts of tank water every 15 minutes or so in order to help your fish adjust.

Conclusion

By now you will have a general idea of which fish and invertebrates you can stock and how many of these will safely fit into your tank. Remember to include factors such as price, availability, hardiness in your decision making process. It would also be worth your while to pay a visit to a pet store where you can have the opportunity of looking at your chosen corals and fish in a real life aquarium setup. 

comments powered by Disqus

Related Content

SALTWATER AQUARIUM ARTICLES

STOCKING THE TANK

The fish you choose to stock your tank is not a decision that should be made lightly. The articles in this category will help you understand the basics of fish compatibility and will provide you with other information you need to make an informed decision when stocking your tank.

Marine Shrimp for the Saltwater or Reef Tank
MARINE SHRIMP FOR THE SALTWATER OR REEF TANK
Marine shrimp can be a useful addition to the saltwater tank - just be sure to pick the right species.
Keeping Moray Eels in the Marine Tank
KEEPING MORAY EELS IN THE MARINE TANK
Moray eels can be a challenge to keep in the home aquarium but they are well worth it.
Top Recommendations for Tank-Raised Saltwater Fish
TOP RECOMMENDATIONS FOR TANK-RAISED SALTWATER FISH
When purchasing saltwater aquarium fish, you need to think about whether the fish are tank-raised or captive-bred.
Hermit Crabs in Saltwater Tanks
HERMIT CRABS IN SALTWATER TANKS
Hermit crabs do more than just add decoration to the saltwater tank -- they can also help to keep your tank clean.
Saltwater Fish Article Database
SALTWATER FISH ARTICLE DATABASE
Articles on dozens of saltwater fish and appropriate care.
Guide for Keeping Anemones in a Reef Tank
GUIDE FOR KEEPING ANEMONES IN A REEF TANK
Keeping anemones in a reef tank can be a challenge if you are not fully prepared.
Stocking Salt Water Reef Tanks
STOCKING SALT WATER REEF TANKS
Learn how to select the right quantity and combination of fish for your saltwater aquarium.
Keeping Lionfish in the Home Aquarium
KEEPING LIONFISH IN THE HOME AQUARIUM
The lionfish is a beautiful but deadly fish that makes a unique addition to the saltwater aquarium.
Sea Cucumbers for Reef Tanks
SEA CUCUMBERS FOR REEF TANKS
Sea cucumbers are found throughout the ocean but they are a popular addition to saltwater reef tanks.
Selecting and Caring for Saltwater Angelfish
SELECTING AND CARING FOR SALTWATER ANGELFISH
Saltwater angelfish are some of the most colorful saltwater fish available.
Keeping and Breeding Mandarinfish
KEEPING AND BREEDING MANDARINFISH
Mandarinfish are a small, colorful species of saltwater aquarium fish.
Tank-Raised Fish for Saltwater Aquariums
TANK-RAISED FISH FOR SALTWATER AQUARIUMS
Stocking the saltwater aquarium can be an exciting challenge, especially when you have so many options to choose from.
Clownfish in the Reef Aquarium
CLOWNFISH IN THE REEF AQUARIUM
Clownfish are one of the most recognizable types of saltwater aquarium fish.
What Are Good Saltwater Fish For Beginners
WHAT ARE GOOD SALTWATER FISH FOR BEGINNERS
What makes a saltwater fish a good candidate for beginners?
Caring for Saltwater Gobies
CARING FOR SALTWATER GOBIES
The Goby family is one of the largest families of marine fishes, having over 2,000 unique species.
The Secret to Keeping Seahorses
THE SECRET TO KEEPING SEAHORSES
If you are looking for a unique inhabitant to add to your saltwater tank, consider the seahorse.
The Benefits of Snails in the Saltwater Tank
THE BENEFITS OF SNAILS IN THE SALTWATER TANK
While snails are often viewed as a nuisance in the freshwater tank, they can serve a valuable purpose in the saltwater aquarium.
Saltwater fish are known for being some of the most colorful creatures in the world.
UNDERSTANDING THE COLORATION OF SALTWATER FISH
Have you ever been dazzled by the bright colors and bold patterns of a school of saltwater fish?
Sea urchins are a great addition to the saltwater tank.
SEA URCHINS IN THE SALTWATER TANK
If you are looking for a unique invertebrate to add to your saltwater tank, consider the sea urchin.
The Achilles tang is one of the most popular tang species.
TIPS FOR CARING FOR TANGS PROPERLY
Tangs are a group of fish that make excellent additions to the saltwater tank.
If you purchase your saltwater fish online you may have a larger variety of species to choose from.
THE BENEFITS OF PURCHASING SALTWATER FISH ONLINE
If you are thinking about buying some new fish for your saltwater tank, think about purchasing them online!
Commonly Available Reef-Safe Fish & Invertebrates
COMMONLY AVAILABLE REEF-SAFE FISH & INVERTEBRATES
Learn about commonly available reef-safe fish and invertebrates that are good candidates for your reef aquarium.
Saltwater Species That Should Not be Kept by Beginners (and Sometimes not Even by the Experienced)
SALTWATER SPECIES THAT SHOULD NOT BE KEPT BY BEGINNERS (AND SOMETIMES NOT EVEN BY THE EXPERIENCED)
Learn about saltwater animals that beginners (and sometimes experts) should avoid keeping.
Establishing up a Clean-up Crew in Your Saltwater Aquarium
ESTABLISHING UP A CLEAN-UP CREW IN YOUR SALTWATER AQUARIUM
Learn how to properly select and establish a clean-up crew in a saltwater or reef aquarium.
Read more articles (24) Aquarium Setup (9)
Saltwater Aquariums
SALTWATER AQUARIUMS
A brief introduction to saltwater aquariums.
Getting The Tank Ready
GETTING THE TANK READY
Creating an ecosystem.
Stocking a Brackish Aquarium
STOCKING A BRACKISH AQUARIUM
A brackish aquarium is an exciting challenge for the aquarium hobbyist.
Types of Saltwater Tanks: Fish-Only, FOWLR and Reef Tanks
TYPES OF SALTWATER TANKS: FISH-ONLY, FOWLR AND REEF TANKS
There are several different types of saltwater aquariums to choose from and each has its benefits and drawbacks.
Setting Up A Saltwater Tank System
SETTING UP A SALTWATER TANK SYSTEM
What to Consider before Starting.
Handy Aquarium Accessories and Devices
HANDY AQUARIUM ACCESSORIES AND DEVICES
There are many accessories and handy devices which can make your life as an aquarium hobbyist easier.
Preparing Saltwater for your Marine Tank
PREPARING SALTWATER FOR YOUR MARINE TANK
Setting up and maintaining a marine tank can be a challenging experience and preparing your saltwater correctly is one of the most important tasks.
Balloon mollies make great additions to the brackish tank.
HOW TO START A BRACKISH TANK
If you are looking for a new challenge as an aquarium hobbyist, try cultivating a brackish tank.
Saltwater versus Freshwater Aquariums
SALTWATER VERSUS FRESHWATER AQUARIUMS
Learn the arguments for choosing to set-up either a freshwater or saltwater aquarium.
Aquarium Maintenance (15)
Saltwater and Reef Tank Cycling
SALTWATER AND REEF TANK CYCLING
Tips on cycling your fishtank.
Maintaining Your Saltwater Tank
MAINTAINING YOUR SALTWATER TANK
Tips for maintaining a saltwater fish tank.
Choosing the Correct Temperature for a Marine Aquarium
CHOOSING THE CORRECT TEMPERATURE FOR A MARINE AQUARIUM
One of the most important things you must to do ensure the health of your marine tank is to achieve and maintain the ideal temperature.
Maintenance Schedule for Reef Tanks
MAINTENANCE SCHEDULE FOR REEF TANKS
Maintaining a reef tank can be a challenge but as long as you keep up with your routine maintenance tasks, you should have no problem.
Why Do Fish Disappear from the Saltwater Tank?
WHY DO FISH DISAPPEAR FROM THE SALTWATER TANK?
There is nothing as heart-breaking as losing a fish but it can be even more devastating when the fish simply disappears.
How to Deal with Marine Fungus in the Saltwater Aquarium
HOW TO DEAL WITH MARINE FUNGUS IN THE SALTWATER AQUARIUM
Fungal spores are present in all aquariums but, if you are not careful, they can become a problem in the saltwater tank.
Salinity Requirements in a Saltwater Aquarium
SALINITY REQUIREMENTS IN A SALTWATER AQUARIUM
The key to maintaining a healthy saltwater aquarium is to strike the right balance in the salinity of your tank water.
Kalkwasser for the Marine Tank
KALKWASSER FOR THE MARINE TANK
Maintaining proper calcium levels is an important part of keeping your marine tank healthy.
Dealing with Hard Water in the Saltwater Tank
DEALING WITH HARD WATER IN THE SALTWATER TANK
When it comes to maintaining a healthy saltwater tank, water quality is extremely important.
The Dangers of High Ammonia, Nitrite and Nitrate
THE DANGERS OF HIGH AMMONIA, NITRITE AND NITRATE
Water quality is extremely important in maintaining a saltwater tank.
Marine algae can be beneficial in the saltwater tank.
THE BENEFITS OF ALGAE IN SALTWATER TANKS
Many aquarium hobbyists assume that algae in the aquarium can only be bad.
Learn how to modify the pH in your saltwater tank so you can correct pH problems if they occur.
HOW TO MODIFY PH IN A SALTWATER TANK
The pH level in your saltwater tank is incredibly important for the health and vitality of your tank.
What NOT to do with a Saltwater Tank
WHAT NOT TO DO WITH A SALTWATER TANK
Learn what "not" to do when starting out with your saltwater fish or reef tank.
How to Remove a Mantis Shrimp From a Saltwater Aquarium
HOW TO REMOVE A MANTIS SHRIMP FROM A SALTWATER AQUARIUM
In this article you will receive an overview of what mantis shrimp are, how they can impact your saltwater aquarium, and how to remove them properly.
Getting Rid of Aiptasia in Your Reef Aquarium
GETTING RID OF AIPTASIA IN YOUR REEF AQUARIUM
Learn about aiptasia in the reef aquarium and how to get rid of it.
Reef Tanks (11)
Reef Aquariums: Is Bigger Really Better?
REEF AQUARIUMS: IS BIGGER REALLY BETTER?
Cultivating a reef tank is an exciting but challenging task - learn more about choosing the right size for your reef tank.
Beginner Coral Species: Low-Light Corals
BEGINNER CORAL SPECIES: LOW-LIGHT CORALS
Keeping corals in a saltwater aquarium can be challenging but these low-light species are perfect for beginners.
How to Care for Marine Blue Sponges
HOW TO CARE FOR MARINE BLUE SPONGES
The blue sponge makes a great addition to the marine tank.
Recommended Species for Nano Tanks
RECOMMENDED SPECIES FOR NANO TANKS
Cultivating a nano tank can be an exciting challenge but unless you choose the right fish for your tank, you may be in trouble.
Bristle Worms in the Marine Tank
BRISTLE WORMS IN THE MARINE TANK
Dealing with pests is an inescapable part of cultivating a marine tank.
Common Myths and Problems Regarding Nano Reef Tanks
COMMON MYTHS AND PROBLEMS REGARDING NANO REEF TANKS
Cultivating a nano reef tank can be an exciting challenge.
Feeding Corals —  Keeping Your Saltwater Invertebrates Healthy
FEEDING CORALS — KEEPING YOUR SALTWATER INVERTEBRATES HEALTHY
If you want to keep your saltwater or reef tank healthy, you need to learn the basics of feeding corals.
Types of Coral for Reef Tanks
TYPES OF CORAL FOR REEF TANKS
Stocking a reef tank can be a challenge because there are so many different types of coral to choose from.
Set-up Guide for a Reef Tank
SET-UP GUIDE FOR A REEF TANK
If you have ever considered starting a reef tank, read this setup guide to make sure you start your reef tank off right.
A nano reef is a miniature reef environment less than 30 gallons in size.
WHAT IS A NANO REEF?
Whether you are looking for a new challenge as a saltwater aquarium enthusiast or you are trying your hand at a reef tank for the first time, a nano reef is a great way to go.
Reef Aquariums
REEF AQUARIUMS
An overview of the reef aquarium along with a short history.
Aquarium Lighting (3)
UV Sterilizers for Reef Aquariums
UV STERILIZERS FOR REEF AQUARIUMS
A UV sterilizer is a valuable piece of equipment to add to your reef tank or fish-only saltwater aquarium.
Tips for Lighting a Reef Tank
TIPS FOR LIGHTING A REEF TANK
When it comes to maintaining a thriving reef tank the type of lighting system you choose is incredibly important.
Saltwater Aquarium Lighting and Heating
SALTWATER AQUARIUM LIGHTING AND HEATING
Kind of lights you need.
Heating and Filtration (8)
Saltwater Aquarium Filtration
SALTWATER AQUARIUM FILTRATION
The type of filtration system you choose for your saltwater aquarium is incredibly important.
Wavemakers for Saltwater Tanks
WAVEMAKERS FOR SALTWATER TANKS
If you want to keep your saltwater tank healthy, you need to consider the ideal level of water flow.
Reverse Osmosis for the Saltwater Tank
REVERSE OSMOSIS FOR THE SALTWATER TANK
If you want to keep a healthy and thriving saltwater tank, you need to start with high-quality water.
Foam Build-up on Saltwater Tank Surface
FOAM BUILD-UP ON SALTWATER TANK SURFACE
Foam build-up is a common problem in the saltwater tank.
Common Problems with Heating in Saltwater Tanks
COMMON PROBLEMS WITH HEATING IN SALTWATER TANKS
Maintaining a stable water temperature in your saltwater tank is important for the health and well-being of your fish.
An aquarium sump can simplify the maintenance of your saltwater tank.
WHAT IS AN AQUARIUM SUMP?
If you are new to the aquarium hobby you may not be familiar with the term "sump".
How to Keep Your Saltwater Aquarium from Overheating
HOW TO KEEP YOUR SALTWATER AQUARIUM FROM OVERHEATING
Learn how to keep your saltwater aquarium from overheating.
What is Protein Skimming?
WHAT IS PROTEIN SKIMMING?
Learn about protein skimming, why it's important, and which aquarists should use it.
Nutrition and Feeding (6)
Top Commercial Foods for Saltwater Fish
TOP COMMERCIAL FOODS FOR SALTWATER FISH
What you feed your saltwater aquarium fish will play a major role in determining their health and vitality.
Tips for Getting Fussy Fish to Eat
TIPS FOR GETTING FUSSY FISH TO EAT
Feeding saltwater aquarium fish can be tricky, especially when your fish refuse to eat.
How to Raise Brine Shrimp
HOW TO RAISE BRINE SHRIMP
Brine shrimp are an excellent source of protein for aquarium fish and they are very easy to raise at home.
Live Foods for Marine Fish
LIVE FOODS FOR MARINE FISH
Feeding your fish a proper diet is the key to keeping them healthy.
Nutritional Needs of Saltwater Aquarium Fish
NUTRITIONAL NEEDS OF SALTWATER AQUARIUM FISH
In order to keep your saltwater aquarium fish healthy you need to understand and meet their basic nutritional needs.
Many saltwater aquarium fish enjoy the addition of fresh vegetables to their diets.
TIPS FOR FEEDING SALTWATER AQUARIUM FISH
What you feed your fish will determine whether or not their reach their full potential.
Saltwater Fish Diseases (5)
How to Treat Saltwater Aquarium Parasites with Freshwater
HOW TO TREAT SALTWATER AQUARIUM PARASITES WITH FRESHWATER
Parasites can quickly become a major problem in the saltwater aquarium if you do not address the issue immediately.
Common Saltwater Aquarium Fish Diseases
COMMON SALTWATER AQUARIUM FISH DISEASES
No matter how hard you try, you cannot completely protect your fish from falling ill.
Good Medications to Keep on Hand
GOOD MEDICATIONS TO KEEP ON HAND
In the event that your fish become ill it is important that you take action to begin a treatment regimen as soon as possible.
How to Deal with Marine Ich in the Saltwater Aquarium
HOW TO DEAL WITH MARINE ICH IN THE SALTWATER AQUARIUM
Marine Ich is a common disease affecting saltwater aquarium fish and, unless you know how to deal with it, it can spread quickly throughout your tank.
Though many saltwater fish diseases are treatable, the best option is to prevent your fish from becoming sick at all.
HOW TO PREVENT SALTWATER FISH DISEASES
There is nothing quite so heartbreaking as losing one of your fish to disease.
Aquarium Decorations (3)
Live rock is the foundation for a thriving saltwater aquarium environment.
CREATING YOUR OWN LIVE ROCK FOR SALTWATER TANKS
Live rock is the foundation for any thriving saltwater tank and it is the base for saltwater aquarium decor.
How to Cure Your Live Rock Before Placing it in Your Aquarium
HOW TO CURE YOUR LIVE ROCK BEFORE PLACING IT IN YOUR AQUARIUM
Learn how to properly cure live rock before placing it in your tank.