Marine Aquaria/Setting Up
Setting up the aquarium is not as simple as it seems. The process is a little more than "Just Add Water."
When setting up your aquarium, it is important to take several factors into account. You will need to consider a proper support for the tank's weight, the nearby environment, and traffic.
Tips if you have a used aquarium
Before setting up a fish tank, you should test if for leaks, especially if you received it second-hand. Simply find a location where you would not mind if it leaked, then place newspapers on the ground. Place your tank on the newspapers and fill it up with water, and let it sit for some time to make sure it doesn't leak. Judging by what area of newspaper gets wet, you can judge where the leak is.
As previously mentioned, the proper support for a tank is necessary. If you are placing an aquarium on something not built for aquariums, you should make sure that the structure is able to support it. Keep in mind, water weighs 8 pounds per gallon so a 100 gallon tank weighs over 800 pounds! An actual store-bought aquarium stand is the safe way to go, and can often be bought in color and wood to match your furniture. Aquarium stands are expensive for a reason. Don't be an idiot like me and think you can go buy wood and build your own (unless of course, you really do know what you're doing). Thrift stores and garage sales are good places to look; get something of a sturdy material, like metal. If you are selecting a stand for a 30 gallon tank, ask yourself if you could picture a sumo wrestler safely standing on it.
You should also consider the floor that you are placing your aquarium on. First, as you will be performing maintenance in the area, you should expect some water to be spilled, but even if you don't, if the tank leaks the disaster is smaller. Secondly, especially if your tank is larger, you must think about if the floor structure is strong enough. Try to place the aquarium perpendicular to the support structure of the floor so that the most beams can share the weight.
The nearby environment includes other things such as lights, windows, radiators, and such. Anything that emits light too close to the aquarium may disturb the organisms as you turn them on and off. Radiators and other sources of heat or temperature change may effect the temperature of the water. Windows are an especially unwise place to put an aquarium. Though corals need bright light, sunlight can contribute to algal growth. Also, warm or cold air from the window can also effect the aquarium.
Another factor to consider is traffic around the aquarium. Fish may be frightened by the moving around of people near the aquarium. It is best to locate the tank in a place to reduce this stress. On the other hand, putting the aquarium in the corner of the house you never visit isn't the best idea either.
Some aquarists actually place their aquarium in the wall, like a natural picture. Though it is a very good effect, there must be some room behind the wall to give access to the aquarium. Also, it means cutting a hole into the wall, which should be considered if you plan to sell the home later.
Putting it together
Now, you've got your tank in the perfect position. Now you can actually start putting stuff inside!
To set up the tank, build from the bottom up. Place stuff that goes under the substrate down first. This can include an undergravel filter or eggcrate. Both of these things are optional, but if you have either, they should be placed first.
Next, the rocks and decorations are placed down. Make sure that they do not wiggle or budge, otherwise they will be more prone to accidents. Some people like to silicon their rocks together to make sure they don't budge, if their rocks are not live and wet. We put the rocks down before putting anything else down to make sure that they form a good support structure, lest your natural monument collapse on you.
After the rocks are all set in place, the substrate is put in, and then all of you equipment that hang onto or attached inside the aquarium. This way you can make sure everything is right without having to get too wet. After everything is in place, it is time to put in the water.
Use a plate or other solid surface and place it on your substrate or rocks. Pour your water directly on this plate. By doing this, the force of your pouring won't kick up the substrate.
Congratulations, your tank is now set-up! But even so, you're not finished yet.
As talked about in the Nitrogen Cycle section, control of nitrogenous wastes is very important. This can only be done with bacteria, and if you just set up your tank, it's probably relatively sterile, which is not quite what we want if we want the nitrogenous wastes to be controlled.
These bacteria can be obtained in a number of different ways. One is live rock or live sand, both which house plentiful bacterial colonies. Another is a variety of products on the market that claim to have these such bacteria in solution, but the dubious claims of these likely snake oils should be taken with a grain of salt. The third is to get some substrate from an already up-and-running fish tank; this could be sand, gravel, or a piece of dirty filter pad. Or ask your friend to save you some dirty water the next time they clean their tank. The fourth is to let your tank sit, and eventually it will seed itself.
In all of these situations, it doesn't do any good for the bacteria if the aquarium has no ammonia; otherwise, these bacteria will starve. In the case of the live rock or live sand, it actually perpetuates its own cycle as organisms off of the rock can die, decompose, and thus produce ammonia. However, in the case of using any sort of product or letting the aquarium passively gain bacteria, you must provide this food for them.
To provide ammonia, there are two main methods besides using live rock and sand. Another is to provide another organic ammonia source, such as a living thing, usually a fish. The fish will produce ammonia that will allow the bacteria to feed; however, if you are allowing your tank to gain bacteria on its own, the time it takes for bacteria to grow to a level that can keep the ammonia safe for this fish may be too long. However, this is a viable option, especially if one uses a relatively hardy species that can withstand higher ammonia or worse conditions, such as a Damselfish. Some people frown upon cycling with the use of fish as the fish experiences some stress as the bacteria build up to handle the ammonia.
Another method to add ammonia to the tank is a method known as Fishless Cycling. In this case, the aquarist uses straight ammonia; ammonia can be found at a dollar store pure. When trying to find "pure ammonia", one should make sure that the ammonia contains no other substances than ammonia and water. A lot of cleaners contain chemicals such as surfactants (that make bubbles), dyes, coloring agents, fragrences, and a whole range of chemicals that you do not want in you aquarium. "Pure ammonia" is clear and smells quite bad, but for a fishless cycle it will do the trick. This ammonia will provide food for the bacteria without endangering a fish. Just add a couple spoons a day of ammonia to the aquarium to allow the bacteria to feed. Never add ammonia to an aquarium unless there is nothing living inside of it, because, as mentioned before, it is poisonous to most living things other than nitrifying bacteria.
After a couple weeks of this, cycling will be complete, and the aquarium should have built up a sizable colony of bacteria that can handle the waste products of the future inhabitants of your aquarium and make sure the nitrogenous compounds are converted to less dangerous forms.