You’re Aquarium Lighting Suggestions:

It is impossible to give you exact lighting require for your aquarium as there are many factors involved and variation in type of lighting available on today’s market. All of the content below are personal opinions and I must emphasise that there is no one best way to light your tank!
Basic Freshwater Aquarium

With the basic freshwater setup the chances are you may not require much light. For example a regular T8 tropical tube would be adequate, or a 5000-6500k compact fluorescent. The PAR produced by these is low so they would be fine for a tank containing low lighting plants. Any aquatics T8-T12 with a Kelvin range between 5500 and 8000K will be fine so long as you don’t have high light dependable plants.

Freshwater Aquarium Lighting
Your freshwater tank requires higher volumes of ultraviolet and infrared light plus a higher PAR output.  Photosynthesis takes place between the range of 420nm blue and 670nm red in the spectrum.  The leaves of your plants appear green as most visible light is present in this green section of the spectrum lying around 550nm. The green light is reflected (thus this is what we see) and the red and blue light is absorbed. (This peak photosynthesis range of red and blue is called PAR)

Multiple bulbs may not be a choice for your aquarium due to space restriction. If this is the case then the best tubes for you to use in your planted tank are 6500K. In the smaller tanks compact fluorescents around this Kelvin are advisable.

In the larger tanks the latest HO T5’s between 6000K and 7000K are a good choice.
These tubes are recommended as they are also used widely in greenhouse use.

If you have a lot of light in your planted aquarium you need to take into consideration the extra nutrients the plant will require because of the rapid growth. Carbon is a common nutrient that you would have to supply to the plants.  This is usually provided by the respiration of the fish you have in your tank. In larger tanks with high volumes of plant life, it may be advisable to use a CO2 system as you would have to supplement the CO2 needed for the plants from another source other than the fish respiration.

Basic Saltwater Aquarium Lighting

A basic saltwater aquarium does not have a high light requirement, but it does have more requirement than a freshwater tank. An iQuatics 10000K White T5 tube is the basic light which can be used for the basic saltwater aquarium. The number of these depends on the size of your aquarium. If you are looking at have corals etc then your light would need to be upgraded.

Basic Reef or Nano Aquarium Lighting

Usually the best bet for these small reef aquariums is the use of compact fluorescents which come in a range of sizes and colour combinations.  The optimum PAR which you would require would come from the lamps around 6500K.

In the larger of the basic reef aquariums HO or VHO t5’s would be recommended.  They are more cost effective if you compare the efficiency and output to that of the regular T8 or T12 fluorescent tubes available.

If your budget for you basic reef tank can afford, then you should never rule out the use of metal halide lighting.  For a nano tank you would in general only require a 70w or 150w halide at a push. If they are mounted onto of the nano tank then a chiller shouldn’t be required due to the air movement around the unit dissipating the heat away from your water quite well.

Advanced Reef Aquarium Lighting

If you are planning on keeping an advanced reef system with hard corals then you may require a combination of LED, T5’s and Halides. (Hard corals obtain their main source of energy from light therefore they need a higher volume and intensity for the flourishing survival).

Depending on the depth of your tank depends on what wattage of halide/halides you would require.  In general 70w are good for a nano tank, 150w are good to up the approx 2ft, 250w halides between 2ft and 3ft and any deeper you would require 400w.

Although many aquarists think that halides are the best and most accurate source of artificial sunlight SHO T5’s can be used for keeping many stony corals, clams and other species which depend on the photosynthesis of zooanthellic algae.

For the best results it is ideal to mix your lighting sources to gain the maximum effect on the corals especially in an advanced reef system, Not only will this save on the electricity costs, it can also reduce the need for an expensive chiller.