Ideal water temperature for tropicals is 75-80 degrees. Buy the best thermometer you can find and check it occasionally. Do not clean aquariums with soaps, detergents, or disinfectants. Scour with non-iodized salt or use special aquarium detergents. Residue may kill fish.
Bad water is indicated by cloudiness, bad smell, or a yellowish color.
Fish may hang at surface or appear nervous. Dechlorinate as local water conditions dictate. Allow water to run from the faucet for at least 2 minutes before drawing water for the tank. Household pipes add metal to standing water. Keep tank out of sunlight.