General Lighting Requirements For Plants
* It was recommended to use mylar emergency blankets (cheap to buy in the camping department of any department store, don't pay for costly hydroponic mylar sheets) make a fairly good reflective curtain to put around an indoor growing area to reflect light back to the plants and to help soften the light escaping from the area so the rest of the room is still livable
-Most vegetables, for instance, grow best in full sunlight
-nearly all plants prefer a dark period each day for normal growth.
Kelvin temperature is a measure of the color of a light source relative to a black body at a particular temperature expressed in degrees Kelvin (°K).
In simpler terms, it is the degree of warmth or coolness of a light source, not with regards to the physical temperature, rather to the visual temperature of the light. The higher the degree K, the more blue, or "cooler" the lamp appears. The lower the degree K, the more "warm", or red the light appears.
Incandescent Plant Grow Lights - POOR
- very poor grow light
- never place an incandescent bulb closer than 24 inches over your plants
- average life span of 750 hours.
Standard Fluorescents - BETTER
- are twice as efficient as incandescent bulbs
-excellent choice for starting seedlings & leaf lettuce, spinach, and herbs
-place no further than 4 inches away from the tops of the plants (burn cool)
-recommended using 1 cool and 1 warm tubes
-average usable life span of up to 20,000 hours
High Output Fluorescents - BETTER
-produce twice as much light as standard
-an 8-tube 4-foot model produces approximately the same amount of lumens as a 400 watt Metal Halide fixture, but with much less heat and the ability to more evenly spread
- produce about 5,000 lumens per 54 watt 4-foot tube
-available in warm (3000K) or cool (6500K) versions. Also available are 2-foot 28 watt tubes that produce 2,450 initial lumen
-average usable life span about 10,000 hours.
-T5 fluorescents were recommended by a fellow aquaponics
Compact Fluorescents - BETTER
- done in “bulb” format, need reflector to efficiently direct light to the plants
- available in warm (3000K) or cool (6500K) versions
- average usable life span about 10,000 hours.
High Output Fluorescent / HID Hybrids - BEST
- combine the incredibly bright cool burning power of high output fluorescents with the penetration that can only be achieved through high intensity discharge technology. The primary advantages to these fixtures is their blend of light colors and broad even coverage.
Metal Halide /High Intensity Discharge – BEST FOR INDOORS
- highly efficient light source (closest to natural sunlight)
-light in the range of 2700 to 5500 Kelvin degrees
- five times more efficient than their incandescent lights
- usable lifespan between 10,000 and 20,000 hours, depending on the wattage.
High Pressure Sodium / High Intensity Discharge – BEST FOR GREENHOUSE
- great ability to enhance the fruiting and flowering process in plants.
- preferred supplemental greenhouse light due to their high efficiency and the fact that plants grown in greenhouses get all the blue light they need naturally
- incredibly long usable bulb life
Light Emitting Diodes (LED)- AVOID
SOURCES
http://www.homeharvest.com/
http://www.ehow.com/how_4678121_set-up-aquaponics-system.html