change the water frequently.Atleast twice a week.

Don´t forget to turn of your heaters before a water change, (or turning them back of afterwards)

Do not buy fish that do not fit the size of your tank. Common pleco's, Oscars, bala sharks go in LARGE tanks.

Test your water at least twice a week

Make sure you have a established temperature before adding new fish

Always cycle the tank in the beginning

Don't overfeed your fish

Keep a clean tank with weekly water changes

Stability in your water is one of the most important keys to a successful aquarium.

Get fish that suit your water conditions. It is much easier on the fish than trying to suit your water to the fish.

Be sure to take the growth factor of the fish you want into account. Some fish will outgrow your tank fast (common plecos, Chinese Algae Eaters)! While some will stay relatively small (tetras, corys).

The tank's background can sometimes really set off the aquascaping in a tank. You have many options here. There are tons of ready-made tank backgrounds that are of picturesque nature scenes, coral reefs, etc. Choose one that you like and one that won't clash with what's going to be in the tank.