Lighting SPREAD question

[SnowManSnow]

How LONG of a tank could a 400w HQI pendant light? Is it like 2 feet ? or is it 3?

B

 

[Ben1]

I think 2' is the norm but it depends on the reflector.

 

[Anonymous]

Depends how high the pendant is.

 

[Len]

Yup, it depends on the reflector. Most will keep spreading out, but get weaker as it spreads. Some have a more spotlight effect, usually in a 24-30" square.

 

[Anonymous]

I use single 400w halides with a big industrial fixture over the 300gal rubbermaid tanks. I find that it works great with the spread of light. Stuff that needs a lot goes in the center and slowly outward and the edges is zoos and mushrooms. It really does wonders lighting up one tub and those are 5' across. Obviously for a display I would go with the standard one every two feet. I suppose you go with three feet if there was no brace to cast shadows.

 

[Anonymous]

do a search on aaolm for sanjay's lighting articles-you will not find a more in depth/detailed measure/analysis of light spread/intensity for all types of bulbs/reflectors and combinations thereof

 

[camaroracer214]

my boss and i built a very unique acrylic tank that's 4 ft long. using a sunlight supply lumen max (i think) with a 400 watt 20k radium, we were able to light the full tank. it's more than enough light.

 

[phillstone]

my 2ft x 4ft x 1ft 60 gal is lit w/ a single 400w rule of thumb is 2ft per light but if its centered ya get full light for center 2 ft w/ gradually less on the 1 ft leftover ends - works good for lower light coral