Bloggang.com : =Neo= - How to Set up a Freshwater Aquarium

Steps

Decide where you want to put your tank - this will determine what size you buy, and whether or not you'll need a stand to go with it.
Choose a fish tank that fits the space you have decided on. (The process is the same for large tanks versus small, so don't worry if you're thinking of going large the first time around.)
Get an aquarium stand that is designed for the dimensions and shape of your tank.
Make sure that the tank comes with a hood (lid), if not, you'll need one of those too.
Choose gravel for the bottom - this is essential to a healthy aquarium. (One pound of gravel per gallon is a good guide for quantity.)
Decide which filtration system you would like to use - the most common and easiest are either undergravel filters or power filters that hang on the back of the tank.
If you choose an undergravel filter, make sure that the air pump you buy with it is strong enough for the size of the tank - in this case, bigger is better.
If you decide to go with a power filter, select one that will circulate enough water for the size of your tank. (Ideally, it should circulate 5 gallons of water per hour [gph], per gallon of your tank capacity. For example: a 10 gal. tank would need a filter that circulates at least 50 gph.)
Make sure you get a heater if one doesn't already come with your tank - the fully-submersible ones are the easiest to use.
Put your tank where you want it to live - once it's filled with water you won't be able to move it, so choose the spot wisely.
Fill the tank with about two inches of water, then wait for a half an hour. If there are any leaks, it's better they show up now, rather than when you have filled the entire thing.
If all is well, open your bags of gravel, and give them a good rinse under running water in a colander - the less dust in the water, the faster it'll clear when the filter is started up.
For undergravel filters, put the filter plate in, and make sure the lift tubes are fitted. (If you have a submersible powerhead, you only need one - with a traditional air pump, two are best for most tanks under 40 gals, one at each end.)
Spread the rinsed gravel in an even layer across the surface of the filter.
Fill the tank with water to just under the rim of the tank - usually a gap of 1" will do.
If you've chosen an external power filter, set it up on the back of the tank in a position where the outflow will evenly distribute the water. Some tank hoods come with pre-perforated cut-outs which make it easier to position your equipment.
Fill the reservoir of the filter with water, and plug it in! Water should smoothly (and quietly) circulate after a couple of minutes.
Attach your pump airlines or powerhead into the appropriate lift tube(s) now, if you've got an undergravel filter.
Plug in the powerhead/pump. Water should start moving vertically in the lift tube(s).
Install your heater (suction cups) on the inside of the tank. Most of the thermostats on new heaters now come pre-set at an acceptable temperature range of 70-77 degrees Fahrenheit (21-25 degrees Celsius).
Plug in the heater and install your thermometer.
Place in any plants or decorations.
Wait for an hour or two, and check that the temperature is still in the safe range, that there are no leaks, and that the water is circulating properly.
Add the water dechlorinator, according to the instructions on the bottle.
Check everything again, and if it's still going fine after another couple of hours, you're done!
Buy fish! Discuss what type of freshwater, tropical fish you want to have with the sales person. They should give you tips on who can and can't get along, and so forth.
Start with two or three fish the first ten days, then get two or three more, wait another ten days, etc. If you put too many fish at once into a new tank, the water will not be able to adequately cycle, and will quickly turn toxic. Patience is the key for the first six to eight weeks.

Tips

5 gallons of water weighs almost 42 lbs. This should help you decide whether or not you have something that the tank will safely sit on. Anything over 15 gals. will almost certainly need a special stand.
If you have a choice of lightbulb in the light fixture, go with flourescent - it shows off fish colors better, and generates less heat.
Don't leave the light on (if you have one) all night - fish DO need sleep. They need a period of darkness for this, because they don't have eyelids to close. And if you don't have any live plants in your tank, only turn on the light when you are home to view the fish. Fish do not need 14 hours of noon day sun, and the additional light only encourages algae.
If using an undergravel filter, consider getting a single submersible powerhead instead of an air pump - they're much quieter, and more efficient. Use the same guidelines for the power filters to select the right size.
Help your tank ecosystem get off to a good start with an bioenzyme starter to help the good bacteria get a jump on things.
If your power filter makes a rattling noise, try wiggling the intake tube - air gets trapped sometimes and makes a racket.
Not all air pumps are created equal - the box may say "quiet" or "silent", but always ask to test one in the store before you buy it!
Buying an inexpensive check valve for your airline tubing can save you having to buy a new pump in the event of a power outage.
Consider cycling fishlessly. An article about this exists on //www.aquamaniacs.net - It takes a while, but saves the lives of fish.
Research, research, research!! Try to find out what the conditions of your municipal water are. There are different kind of fish suited to live in "hard" or "soft" water, and fish living in the correct water conditions will live longer and be more healthy. Unless you are willing to treat all the water going into the tank (can be expensive and/or time consuming), choosing a setup adapted for your local water can really make your life easier!
If you're having a hard time keeping the tank clear, consider using live plants. They keep the tank from getting murky and look nice. Just make sure that you buy them from a pet store so that they won't harm the fish. "Algae Eater" fish are also possible to use, though they may cannabilize smaller fish if they grow too large.

Warnings

Don't put the tank in or close to a window - this will cause the water to overheat, and also encourage algae to grow.
Resist the urge to buy a lot of fish as soon as you set up your tank! The conditions in a fledgling tank can fluctuate a great deal, which can be lethal to fish.
Don't put anything in the tank as a decoration that has ever been in contact with any soap or cleaners of any kind.
Real sea shells that you found on the beach could be toxic to your fish - remember this a freshwater tank.
NEVER clean the tank sides with any chemical cleanser or soap - window cleaner, bleach, even dish soap are extremely toxic to fish, and can actually be absorbed through the glass.
Try to avoid lifting an empty tank by its rim - the rim may break or come off, which will compromise the structural integrity of the tank.
Don't turn on your heater when it's dry - the glass is very thin and it will break.
Some pet stores do not train their staff well - if someone tells you it's OK to put guppies together with most cichlids, go somewhere else! (There are some peaceful cichlids, but that's another page...)
Never buy fish if they have any sores, blemishes or other defects - chances are they sick and won't survive.
Do not buy a fish from a tank that has a dead fish in it.