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Saltwater tanks

This introduction to saltwater aquariums has the beginner aquarist in mind. There are many reasons for setting up a saltwater aquarium, not least of which is its beauty. The beautiful colours of fish and coral, interesting algae, the soothing sound of bubbling water and the fun involved in creating a fabulous marine world are all reasons why keeping saltwater aquariums gives people so much fun and pleasure.

​For the beginner, even a brief introduction to saltwater aquariums can seem a bit daunting. This is because not only are marine systems a bit complex to set up and maintain, they can also be expensive. Saltwater aquariums are not for everybody and even the simplest marine tank can cause headaches. Fish keeping can be tricky and marine fish in particular take a lot of time and effort to keep healthy. Marine species are far more sensitive to water quality and temperature changes so you will need to be informed about the needs of all your fish as well as the tank itself. Saltwater aquariums require patience and a degree of know-how to make it work. You will also need to make sure that you can afford to keep the tank in a healthy state.

The saltwater aquarium you choose will depend on your aim for the tank and your personal preferences. There are many different options available in terms of the fish and animals you can keep in your tank, as well as the equipment you can choose from. Some saltwater aquariums are not suited for the absolute beginner.

The first thing to decide when setting up your saltwater aquarium is what kind of fish do you want to keep. The next step is finding out as much about each one as you can. Not all marine species are suited to beginners so you might have to adapt your wish-list to suit your level of expertise. Never take on species that are for advanced fish keepers or you could well run into trouble.

There are two main kinds of saltwater aquariums, namely: • fish only • fish only with live rock or reef tanks.

The first is probably the easiest saltwater aquarium to attempt. This is because in saltwater aquariums of this nature, lighting is not really an issue and you can use a simple tank with its usual equipment and only a few extra bits like protein skimmers, powerheads and live rock or sand.

These kinds of saltwater aquariums will usually be either a community tank containing species like clownfish, damselfish, gobies, wrass, and dottybacks, or an aggressive tank where you will find species like lionfish, triggers and larger predatory species. Before you choose your fish, make sure you know EXACTLY which species live well together to avoid your tank turning into a complete massacre. If you are a novice to saltwater aquariums, go for the largest tank you can afford and start with a tank that is at least 38 litres in size. This is because most – if not all – of your fish will easily outgrow a tank and bigger saltwater aquariums are easier to keep in tip-top shape.

Most important to the health of saltwater aquariums is water purification. Even the smallest amount of impurities in the water can hurt your fish. Remember, most of these animals are found in natural reefs where the water is very pure, so you will need to make sure the water in your tank is clean at all times. The best bet for any size tank is an RO/DI (reverse osmosis/deionisation) system. Filtration is quite complicated in saltwater aquariums but this depends to a large degree on the fish species you intend to keep and how many. In a fish only tank you can use a freshwater filter, for example canisters and power filters, and you can also try a wet-dry trickle filter. If you decide to keep a reef tank, you might want to use a natural filtration system like live rock or sand.

Protein skimming is also important in saltwater aquariums and strongly recommended, especially if you have lots of fish in your tank. A protein skimmer uses foaming bubbles to separate fish waste that floats up to the water column from the water’s main flow.

The foundation in your tank will require the laying down of live sand. Sand doesn’t only act as a substrate, it is also the breeding ground for millions of vital bacteria. These bacteria help the nitrogen cycle to work efficiently. The sand is also home to the small animals that help control the waste products in your tank. The best sand for saltwater aquariums is calcium carbonate (aragonite) but you can also use silica and quartz sands.

Let’s move on to the lighting in saltwater aquariums. In a fish only or fish and live rock tank, lighting is not really an issue. In a reef tank, however, it is critical. This is because light is needed for most corals and anemones to grow. Special lights are needed for a marine tank so use one of the following: • power compact fluorescent (PC) • very high output fluorescent (VHO) • metal halide (MH).

Remember you will still need to cycle your tank and perform the necessary water quality testing before you add any of your livestock.

So there you have it – the basics of what to start thinking about as you set up a saltwater aquarium. We suggest doing plenty of further research to make sure you know exactly what you are doing before you get started. Marine tanks are not for everyone, so make sure they suit you before you spend a lot of money.

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