2. Temperature On average, most tropical aquariums do best with temperatures ranging from 23 to 28 degrees Celsius (73-82 degrees Fahrenheit).

3. Salinity Salinity is a measure of the total amount of dissolved salts in seawater. It is measured in parts per thousand (ppt or 0/00). The average salinity of the ocean is around 34 to 37 ppt.

4. Marine aquariums are also measured in specific gravity
Marine aquariums are also measured in specific gravity. Specific gravity may be defined as the ratio of the density of the liquid to the density of water. Since density of liquid varies with temperature, so does specific gravity.

5. The specific gravity of seawater at 35 ppt is 1. 026
The specific gravity of seawater at 35 ppt is The proper range for a marine aquarium is to

6. pH pH is an abbreviation for pondus hydrogenii which also stands for "Power of Hydrogen." Pure water has a pH value of 7. As the scale drops towards 0, the solution becomes more acidic. As the scale rises toward 14, the solution becomes more basic.

7. Filtration Three Types of filtration: There are three major types of filtration used in marine aquariums -- mechanical, chemical and biological.

8. Mechanical- The physical separation of large floating particles from the water
Chemical- The removal of harmful chemicals by activated carbon or other chemical through chemical reactions
Biological- The removal of waste products by natural bacterial decomposition and removal of chemicals by absorption

9. Set-Up a. The aquarium. An aquarium of 76 liters (20 gallons) or more is recommended for marine systems. For a freshwater system, it is recommended to begin with a 38 liter (10 gallon) aquarium.

10. The filter. The types of filtration elements described in this section can be used in both freshwater and marine aquariums. An under gravel filter with at least one or two airlift tubes is advisable for most large systems.

11. Outside filters. consists of a plastic compartment that hangs on the outside of the aquarium is another good filter to use. It pulls water from the aquarium and runs it through both a filter fiber and activated carbon. This also does a good job of circulating the water and is the best option for most home aquariums.

12. The gravel. Most types of gravel will work for a freshwater system
The gravel. Most types of gravel will work for a freshwater system. The gravel should be 1-3 inches thick on the bottom to provide the correct biological filtering capacity of the aquarium.

13. Air. The size of the air pump depends upon the size of the aquarium in use. An air stone should be placed at the end of the tubing and placed in the airlift tubes. Powerhead pumps also help to circulate water.

14. Heater. The temperature of the water is very important
Heater. The temperature of the water is very important. A constant temperature is recommended. Tropical aquariums do well at temperatures of 23 to 28 C (73 to 82 F). Normally the heater should be two watts to every liter in the aquarium.

15. Lights and reflectors. The aquarium should be covered at all times
Lights and reflectors. The aquarium should be covered at all times. The covers reduce evaporation and also keep the fish from jumping out of the aquarium. If you have a saltwater aquarium, the hood should be a noncorrosive material. It is advisable to choose a hood with a florescent lamp.

16. Establishing biological filtration
Establishing biological filtration. Once the aquarium is in place, it should run for at least 24 hours before adding any animals. The levels of pH, salinity, temperature and ammonia should be checked to be sure they are all at acceptable levels.

17. The addition of live plants or one small inexpensive fish may help to initiate the biological filtration. Once all levels are acceptable for your particular style of aquarium, fish can be added to the aquarium.