Saltwater Aquarium Types - FOWLR, Fish Only with Live Rock, Reef Tank

This is a general introduction into the three main saltwater aquarium types: Fish Only, FOWLR (Fish Only with Live Rock) and the Reef Tank Setup. When getting started with saltwater it is recommended to get the biggest tank you can accommodate. Bigger tanks give you more room for error when it comes to water quality.

Again, there are basically three types of saltwater aquarium setups:

Fish Only

This is the least expensive type to set up because you don't necessarily need the better lighting that the other setups require. Check out the Saltwater Aquarium Setup page to get an idea of the equipment needed, minus the live rock mentioned in that article.

In my opinion, even though this is the least expensive setup, a saltwater fish only setup is not necessarily the easiest to get started with. Getting started may take a little longer than the other setups while waiting for the nitrogen cycle to complete. Saltwater fish only tanks also require more frequent tank maintenance than FOWLR tanks. This means that you will need to stay on top of those water changes to remove the nitrates that are constantly accumulating. Having a water test kit is a necessity when keeping saltwater tanks. You will need to periodically monitor the ammonia, nitrite, nitrate and pH levels. These readings will give you a good indication of the water quality inside your tank. It will also give you an idea of how often you should be performing those water changes.

As the name implies, this saltwater fish only tank setup is really for keeping fish only. You may be able to keep a few snails or hermit crabs to help control any algae problems. There are generally two types of fish only tanks. Community type tanks and semi-aggressive type tanks. The community tanks house species that will get along well with the other species in the tank. Semi-aggressive tanks usually house solitary individuals from different species. Unless you have an extremely large tank, it is normally not recommended to get multiple fish from the same species.

These saltwater fish only setups are rapidly falling off in popularity because of the great biological filtration functions that live rock can provide. We discuss FOWLR setups next.

Fish Only with Live Rock - FOWLR

This setup is the same as a Fish Only with the addition of live rock and better aquarium lighting. Check out the Saltwater Aquarium Setup page for more detailed information on this type of setup. The use of live rock has really taken off in the past decade because it really is the best form of natural biological filtration for the saltwater aquarium. It is called "live rock" because of the creatures and organisms living on the inside and on the surface of the rock. It can be very interesting to the look at the organisms and algae growing on the rock.

Getting good live rock, such as Fiji rock, can be expensive and may even be the most expensive part of setting up a FOWLR tank. A rule of thumb for setting up a tank with live rock is 1 to 2 pounds per aquarium gallon. Currently, live rock is going for about $7 per pound, so a 55 gallon tank would need approximately 82.5 lbs (using 1.5 pounds/gallon) or around $578 to get started. This price is just an estimate and the price may be much higher or lower in your particular area.

What makes live rock so good? The porous nature of live rock means that it comes packed with all types of tiny creatures and biological organisms that aid in the nitrogen cycle. The dense, porous material inside the live rock helps rid your aquarium of nitrates. You will still need to monitor your water parameters regularly with a FOWLR aquarium and perform water changes as needed. You will also need to add supplements such as iodine, calcium, strontium, magnesium and others, to the water periodically. Live rock helps maintain stability in a FOWLR saltwater aquarium and it can become a food source for your invertebrates and your fish.

Reef Tank

The reef tank setup is primarily geared towards invertebrates, corals and anemones. The fish in this type of tank are sometimes just an afterthought. "Oh yeah, there's a fish in there". Reef keepers are usually more interested in keeping their corals and anemones growing and this means monitoring water parameters weekly if not daily. These invertebrates, corals and anemones can be very expensive and very hard to keep. It also should be noted that mixing various coral species and motile inverts (like anemones) is usually not a good idea.

Reef tanks are usually set up by more experienced hobbyists because these tanks require excellent water conditions, extremely high lighting levels (expensive), water supplements, reverse osmosis and/or deionized water (expensive), and excellent filtration (usually live rock).

If monitoring your water parameters on a daily basis and spending a lot of money is your idea of a good time, then you should look in to setting up a reef tank. Seriously though, if you are just getting started with saltwater, you should probably leave the reef tank for a future time when you get more experience under your belt. We don't want to discourage you from setting up a reef tank, but we do want to make you realize the amount of research and effort that goes into getting one of these set up. If you've been doing things correctly with your other tanks you are already familiar with researching fish and equipment. Starting with a FOWLR to learn the ropes and seeing if you really like the hobby first before investing in the more expensive reef tank setup can be a good route to take. When buying your FOWLR equipment just keep it in mind that if you like the hobby you will most likely be turning that FOWLR into a full blown reef eventually. Just a warning. :) A reef tank can be very rewarding and breath taking to look at when set up correctly.

You may also come acros something called a nano cube setup. These are very small tanks, typically something less than 30 gallons that are used for small reef tanks for housing corals and other saltwater inverts. These are very cool looking but take a lot of work monitoring water quality and correcting as needed.

Finally, to gain a better understanding of the cost differences between running a freshwater, saltwater or a reef tank, check out the Freshwater vs. Saltwater Aquarium page for more information.

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