Whenever new fishes are added into a fish tank, they are subjected to shock which can kill them. Shock from the temperature changes and chemical differences in water chemistry between where they were last kept and the new environment. Slight variations can be tolerated but each species have different degrees of tolerance. Even same species have different tolerant levels. The basic solution is to limit or lessen as much of the shock as possible. To introduce new fishes into your tank, always float the plastic bag of your fishes in your tank for at least an hour. This is to climatize the temperature between your fishes in the plastic bag with that of your fish tank. After that, add equal volume of water from your tank to the plastic bag of fishes and float for between 15 mins to about half hour. This is to minimize shock from chemical differences like differences in pH, Hardness, salinity, etc.

When a pair of fish is ready to breed, they will usually do so without any external help. This will of course require a female ripe with eggs and a young mature male, depending on species. Egg scatters, like goldfish, tetras, barbs, Rasboras, etc., usually have more males to each female. While most other egg layers like to make their own choices to pair-up (just like humans). Breeding usually takes place in the morning when the water temperature is cooler and the distractions, from noise and prying eyes, are less. To induce spawning, when you have a ripe pair of fish, change 10%-20% of water the night before you want them to lay their eggs. You should add RID-ALL BLACKWATER to keep the pH at a comfortable 6.5 for soft water fishes, and also to replenish the trace elements needed by most soft water fishes.   

You should set-up with a tank as large as your budget or as much as as your space permits. A good choice to start-up is a 30 gallon tank (about 36 x 16 x 16 inches) although a bigger tank (48 x 18 x 18) will allow for more fishes and better aquascaping. Small tanks are less forgiving when you make mistakes, like overfeeding, as the volume of water in question is lesser and therefore changes in pH can be faster and more lethal. 

You will need a good strong air pump, a filtering system, lighting, plants, gravel, some decorations – like drift wood. For a community tank, use an undergravel filter. As the name implies, a filtering plate is placed under the gravel or sand. An uplift pipe than forces air up the tube which inturn forces water through the gravel/sand into the tube and is uplifted by the air.