Reef keeping can be very expensive. This is true in terms of:
and emotional investment.
At the same time, what a thrill it is when success is obtained. Reef keeping combines the riggers of science with the art of beauty in a splendid harmony. A tank in equilibium, with fish arrayed in brilliant colors and corals growing with extended polips can be breathtaking.
First, reef keeping is not for everyone (note the expenses above). If you can't afford it in time, money, energy, patience, or emotional investment, then you can still enjoy the beauty and awe at public aquariums, local fish stores (beauty varies), or the tanks of friends and family members.
If you're still considering reef keeping, or are already in the throws of it and are looking for help, I'll provide my best insights here. Please understand, I am NOT an expert. I've kept salt water tanks for many years with plenty of successes and failures. Don't use the resources and ideas here, or any where else, for that matter, as your sole resource. The internet is filled with information about successful reef keeping. Read from many and varied sources. You will read contradictions. Some articles may make it appear simple and easy. Others are so technical that the information may be meaningless. Keep looking, there's more out there.
Let's start with some simple reef keeping philosophy. Reef keeping is the attempt to have a beautiful little piece of the ocean in your own home or office. Sounds simple enough, right? 'Little,' is the problem. The ocean is not little--it's huge. And our huge ocean has stayed in a life supporting equilibrium for a very long time. I don't care how large the aquarium--large public display aquarium's included--no aquarium compares to the size of the ocean nor in it's capacity for self sustaining life support. The more we learn, the more we can approach the conditions of the ocean in our micro-enviroments. The better reef keepers are making great progress. Some critters that in the past were not ever successfully kept in an aquarium environment are now being kept successfully, and even thriving.
There are many parameters that can be maintained readily in a tank environment. Other parameters are difficult to maintain or even measure. A very important aspect of the ocean, and our little mini-oceans, is the microbiology therein. Bacteria's, algea's, etc., etc., not only vary tremendously from environment to environment, but they also change over time. It may be fair to say that no two aquariums are identical in this regards. Like a fingerprint, there are just two many possibilities and variables to completely control the microbiological environment. Yet, the success and beauty of the tank is completely dependent upon the microbiology of the tank.
The ever challenge of maintaining this equilibrium can strain anyone's patience. In reef keeping, good things always take time but bad things can happen nearly instantaneously!
When considering the size of the reef tank there's a lot that goes into the decision. Larger tanks tend to be more stable--ie, some bad things don't happen quite as quickly. Larger tanks allow for more fish and invertebrates. Some animals cannot thrive in smaller tanks and require larger ones. The larger the tank the more like a coral reef the habitate can be made, including larger teritories for the more territorial creatures and more and better hiding places. Some fish could never live together in a smaller tank but could live together in a larger tank.
On the other hand, the larger the tank the more expensive it will be. Other considerations include the weight of the tank and whether it would be supported. Currently I am running a 60 gallon tank on the ground floor of my home. I've not tried a nano tank (very small reef tank) but I have heard of some great success with nano tanks. They can fit anywhere and are much less expensive. Expect to have to spend some time on it to keep the parameters stable.
When first setting up a tank a lot can go wrong very quickly. Fish waist and uneated food raises the ammonia level in the tank rapidly. Ammonia is toxic to the fish and the invertabrates. Fortunately, ammonia is converted to nitrite by certain types of bacteria. In a new tank, those bacteria may not be in sufficient quantity to convert the ammonia as fast as it is rising. This is known as, 'new tank syndrome.' One of the goals of a new tank is to get the ammonia down to 0. Nitrite, what ammonia is converted into, is also toxic. First, new tank owners may see a spike in ammonia and then a spike in the nitrite levels. Nitrite will be converted to nitrate by other bacteria. It is critical that a tank have a good load of both types of bacteria to keep the toxic ammonia and the toxic nitrite to 0. Nitrate is not as toxic as ammonia or nitrite, but in a reef tank nitrate levels can be one of the biggest problems long term. Most fish can handle a certain degree of nitrate in the water, but some invertibrates, such as some corals, do not handle elevated nitrate levels well at all. Most reef keepers aim to keep ammonia, nitrite, and nitrate as close to 0 as possible. Nitrate is not so easy to get rid of as ammonia and nitrite. There are bacteria that convert nitrates into nitrogen gas that then bubbles harmlessly out of the tank and into the air. These types of bacteria are known as anarobic, meaning they thrive in an environment without oxygen. All of the fish, corals, invertabrates, etc. require oxygen in the water in order to live. This sets up one of the first dilemas of reef keeping--long term water quality.
Certainly regular water changes are required in successful reef keeping. This is both to keep the water in good quality and to add a continuous amount of the necessary salts and trace elements that a good salt mixture provides. But, a tank high in nitrates is hard to water change away. Water quality starts with pure water and an excellent salt mixture. I use distilled water and reef crystals and mix them to a salinity of 1.025 for my tank. When setting up a new tank, the first step is to get the water mixed and add it to a deep bed of live sand. Live sand is sand from the ocean that has been preserved with the ocean bacteria living on the substrate. The reason for the deep bed is that the anaerobic bacteria that convert nitrates into nitrogen gas can live at the bottom of a deeper sand bed. Also, other critters that will make the tank interesting over time will also enjoy burying themselves deep into the sand. I suggest that it is worth the expense to have the deeper sand bed.
With water and fresh live sand in a tank, in may look like a fish tank full of milk! I'm not sure if rinsing the live sand is a good idea or not. For one, you don't want to rinse away the good living organisms. And two, you don't want to introduce things from your water supply that are unwanted. Over a period of days or weeks, I'm told that the small particulate sand matter will drop out of the suspension and the water will be clear. What I've done is simply put a carbon cartridge overhanging filter on and let it grab up the particulate matter. In a few days the tank is nice and clear.
At this point you will want to have a few other things going in the tank. Reef tanks need flow, meaning the water shouldn't be still. This helps with gas exchange--keeping the water oxygenated--but is also important for the health of the fish, and will eventually be critical for the life of corals. From experience, I recommend magnetic and not suction cup attached flow pumps. Suction cups tend to find there way to an unsuctioned state and then the tank can have sand blowing all over the place. You'll need a good heater that is designed for the size of the tank and an accurate thermometer. I keep my tank at 78 degrees farenheit. Before you introduce any living things, other than the live sand, make sure that the flow and the temperature are working perfectly. You'll also need good lighting. There is a lot of material and a lot of opinions on what constitutes appropriate lighting. Corals, especially, require correct lighting to live and expecially to thrive. For now, keeping it simple, I use LED lighting. It is powerful, does not require much electrical juice, and doesn't heat up the tank much at all. LED's for reef tanks are getting better and less expensive. On my 60 gallon setup I have two 30W 15000K lights and four 10W 450nm lights. I vary when one, both, or the other is used. Corals at night with just the blue light on is a sight to be seen!
I have not done this up to this point but will strongly consider it in the future: install a refrugium under the tank to house macro-alge and for protein skimming. I can't offer any advice on how to do it, but there are many resources out there that can. The idea is to pump water from the tank into the smaller tank underneath. The smaller tank would have macro-alge growing 24-7 with the lights always on. Alge lives on the waste of the fish. Basically, it loves nitrates and phosphates. It can grow and thrive and take over the entire bottom tank without causing any problems, being eaten by the fish in the main tank, or becoming unsightly if kept in a seperate refugium below. Also, with no animals in it, you can keep the lights on continually. Macro-alge doesn't require any dark time to thrive. Protein skimming is also important to a clean thriving reef tank. It can be installed in the refugium instead of on the main tank, keeping it nicer looking, minimizing overflow problems, and keeping the sound down. Since I don't have a refugium I keep macro-alge growing in my main tank and I have a protein skimmer attached on the side. These two things, along with regular water changes can keep the water quality good.