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Types and Styles of Saltwater Aquariums!

This week we are giving you an overview of the various saltwater aquarium styles so that you can find what you are really interested in! You may already know about corals and have some fish you like, but we will show you how vast and unique the saltwater aquarium hobby is, and give you a bunch of options that you may have never heard of before. 

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Table of Contents

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Different types and styles of Saltwater Aquariums:

Fish Only and Fish Only With Live Rock (FOWLR)

As the name suggests, this is a style of saltwater aquarium where your focus is just the fish, without any corals, anemones, sponges, etc. You can choose to have artificial decorations, like fake corals and rocks, or you can go for a more natural look by using real rocks.

The latter option, using real rocks, is what is referred to when talking about FOWLR. This is because these rocks have a greater ability to house various bacteria and critters that help the biological diversity and biological filtration of the saltwater aquarium. This is why they are called “live rocks” and are often preferred in all types of saltwater aquariums. 

A saltwater aquarium with only fish is a great starting point for beginners, because fish are more resilient than invertebrates like corals, anemones, shrimp, etc. You can gain experience and your tank can gain biological maturity while you keep it a FOWLR. Then, when you decide to make the leap to keeping corals and other such things, your saltwater aquarium will be so well established that you won’t have the many issues that others might when starting!

It is worth noting, that some people keep FOWLR saltwater aquariums due to their relative simplicity and ease of care, compared to an aquarium with corals. However, in some cases people have aggressive fish or other inhabitants that are not compatible with a coral reef style aquarium. 

These are often called Predator FOWLR aquariums. These fish may include ones that will eat smaller fish, eat corals or anemones, or eat crustaceans like shrimp and crabs! Depending on the size of the saltwater aquarium, it may even include sharks or stingrays. These are not necessarily hard to do, but make sure to do your research. If you think you might want to try corals, avoid these type of fish! 

Soft Coral and Large Polyp Stony (LPS) Coral

Having corals in your saltwater aquarium is the goal for a lot of aspiring hobbyists, but did you know that there are multiple types of coral? In the saltwater aquarium hobby, we generally say that there are three types: Soft corals, LPS corals, and SPS corals.

The soft corals do not have a rigid skeleton, whereas LPS and SPS do. The differences between LPS and SPS is the size of the polyps, basically their little mouths, and the extensiveness of the skeletons. LPS have bigger polyps and smaller skeletons, while SPS have smaller polyps and more extensive skeletons. 

When it comes to the saltwater aquarium hobby, the soft corals and LPS corals are considered easy and beginner friendly, while SPS corals are for more experienced hobbyists. However, there are many exceptions to this rule and you can certainly have SPS if you would like to! 

Due to soft corals being easier to take care of, you often see beginners start with them. These corals grow fast, are usually very resilient, and do not require intense lighting, perfect stability, or really high flow. LPS corals are usually similar, except that they grow slowly.

Soft corals are also known for their ability to sway in the currents, giving a very lively feel to an aquarium dominated by soft corals. It is also the best option for those on a budget or worried about losing corals due to mistakes, as they are usually cheap, grow fast, and hard to kill. As well, you do not need to worry about your water parameters as much. 

If you want to add some variety, you can then add in some LPS corals, and they will likely thrive in the same conditions as your soft corals! Just do your research and make sure all your water parameters are correct. These corals are easier to take care of, but you want to make sure you are giving a good life to them and letting them thrive, not just survive!  

Small Polyp Stony (SPS) Coral

@7_feet_of_reef on Instagram
@7_feet_of_reef on Instagram

As we mentioned before, these are corals with small polyps and extensive skeletons. These corals can have some amazing color varieties and grow into large colonies that resemble what you would see in a real coral reef. SPS corals also generally require high water flow, high intensity lighting, very clean water, and really stable water parameters!

Due to these requirements, it is not uncommon to see saltwater aquariums that are practically only filled with SPS corals, with maybe a handful of LPS corals. These tanks do not necessarily have the lively swaying, but you often see beautiful structures and colors, accompanied by a few beautiful and helpful fish.

Generally, a full on SPS aquarium will require you to do more research and to have more fancy gear, but you can certainly do it even as a beginner. As with other corals, some SPS are hardier and easier than others. With enough preparation, there is no reason you wouldn’t be able to keep a beautiful SPS dominant saltwater aquarium!

Mixed Reef

The mixed reef style of saltwater aquariums is what most hobbyists are eventually drawn to. As the name suggests, here you may have a mix of all three types of corals, but also anemones, sponges, clams, macro algae, and even non-photosynthetic corals! This style gives you the most flexibility to create your dream aquarium, and not be as limited in what you decide to put in it.

However, due to the fact that you may be mixing various things in one aquarium, it is even more important that you research and plan you livestock choices ahead of time. There is always a chance that some things won’t be compatible, and that the ideal environment for one thing does not work for another!

Macro Algae and Seahorses

@tigahboy.h2o on Instagram

Macro Algae have been growing in popularity in recent years within the saltwater aquarium hobby. Many people started using them in refugium’s or “algae turf scrubbers” as a method of natural filtration. However there are many beautiful varieties of macro algae that can be used in a display aquarium, such as the one above from @tigahboy.h2o on Instagram! 

Not only are these unique and new to the hobby, but they are also generally easier and less expensive to keep and start than a saltwater aquarium with corals. This is because Macro Algae itself is cheaper, grows faster, and is much less demanding. This style of aquarium might be a good transition for those coming from the freshwater planted aquarium side of the hobby!

You can also have corals with macro algae, and other things, as we mentioned in the mixed reef section. The other thing worth noting is that you can have Mangrove trees in your aquariums! They help filter the water and grow out of the aquarium, giving it a beautiful and natural aesthetic. Just like macro algae, there has been  an increase of people putting Mangroves in their aquariums.

Finally, if you ever wanted seahorses or other such gentle and unique fish, the macro algae aquarium is the perfect setup for them. Seahorses are one of those fish in the saltwater aquarium hobby, where the whole setup needs to be based around their unique needs. So, if you really want to keep some beautiful seahorses, do your research!

Coldwater and Non-Photosynthetic (NPS)

The final styles of aquariums we will be talking about today are coldwater and non-photosynthetic saltwater aquariums! These are also unique, but have a devoted niche community within the saltwater aquarium hobby. However, unlike macro algae aquariums, these styles will be a bit more expensive and complicated to have.

As the name implies, the Coldwater aquarium contains species from non tropical zones. This includes most of the things you would find in the kelp forests of the West Coast or in the waters around the U.K. However, for this setup you will preferably have an acrylic aquarium and you will almost certainly need a chiller, which isn’t a cheap piece of gear. 

These can be just as colorful and interesting as a tropical coral reef style aquarium, but the requirements are certainly a bit different. Closely related is a saltwater aquarium dominated by non-photosynthetic beings. This would include corals, clams, anemones, oysters and scallops, sponges, worms, and more! 

These can be either cold water or tropical, and you can certainly include some of these non-photosynthetic beings in a mixed reef aquarium. There are some people that choose to have a tank full of these unique animals, and these setups can look very cool and gorgeous. The difficulty of this style is that it requires a lot of food, often special and alive food, and it requires very good filtration. 

Just because these last few styles of saltwater aquariums are more niche, requiring a different set of gear and work, doesn’t mean that a beginner can’t try them out!