Hqi Lighting
- Thread starter AR325
- Start date
phlipper84
New member
I think you can only go with 150 or 250 with hqi. Also what are you planning on keeping?
dgin
New member
Adrian,
It would be difficult to get a HQI bulb (with a pendant) to give the proper light spread for a 48" wide tank. The general rule of thumb is 1 MH fixture for a 2'x2'. You would need two MH fixtures for your tank, otherwise, you may get some shadows and have some dimness in parts of the tank because MH are a single point light source.
As someone already posted, you would need to go 150w, 250w, or 400w for HQI. 175w is a SE (mogul) bulb.
It would be difficult to get a HQI bulb (with a pendant) to give the proper light spread for a 48" wide tank. The general rule of thumb is 1 MH fixture for a 2'x2'. You would need two MH fixtures for your tank, otherwise, you may get some shadows and have some dimness in parts of the tank because MH are a single point light source.
As someone already posted, you would need to go 150w, 250w, or 400w for HQI. 175w is a SE (mogul) bulb.
grenaria
New member
The K stands for Kelvin, which is a measurement of temperature. The relationship between temperature and color is called blackbody radiation. A blackbody is defined as a theoretical perfect absorber and emitter of radiation, i.e. it absorbs and emits no photons from it's existance. A blackbody of a given temperature will emit a known light curve (Plank's law), predictable intensity for a given frequency (color/energy) of light. Now these bulbs don't actually give off perfect blackbody light curves (not even close), but blackbody light curves have three features, Plank's law, Wein's law (a single intensity peak at a predictable color), and Stefan-Boltzmann's law (energy flux proportional to temperature to the 4th power).
So by looking at the shape of the light curve, the peak intensities, and the energy flux from a light bulb, along with a little fudging they can claim their light curve is close to a black body of a given temperature.
The sun is not a perfect blackbody, but it is pretty close to one with the temperature of the surface of the sun (~6000K). However, water absorbs red light preferentially, so the deeper you go, the "hotter" the apparent spectrum.
So by looking at the shape of the light curve, the peak intensities, and the energy flux from a light bulb, along with a little fudging they can claim their light curve is close to a black body of a given temperature.
The sun is not a perfect blackbody, but it is pretty close to one with the temperature of the surface of the sun (~6000K). However, water absorbs red light preferentially, so the deeper you go, the "hotter" the apparent spectrum.
aztbs
Active member
Nice post g!
I run 2 x 175SE fixtures over my 55 gallon (48l x 13w x 18t) tank with Spider reflectors and the coverage is perfect. I run 20000k bulbs without actinic supplementation and it is pretty blue.
For softies, 175's are probably fine even with the depth of the tank, but one will leave very dark ends.
I run 2 x 175SE fixtures over my 55 gallon (48l x 13w x 18t) tank with Spider reflectors and the coverage is perfect. I run 20000k bulbs without actinic supplementation and it is pretty blue.
For softies, 175's are probably fine even with the depth of the tank, but one will leave very dark ends.
