Is my hps as bright as it should be?400w

gubblebum

Well-Known Member
Hi basically I seem to remember that when I first got this bulb like a year or so ago the light meter went a lot higher! If i put it directly under the bulb 20 inches down it now reads 2000 lumens. Its a 400w hps. Does anyone else have a light meter to check this? Its inside a cooltube which will also probably reduce it somewhat and on a lumatek digi ballast which i hoped would ballance this :)
 

richjames

Well-Known Member
A 400w hps bulb puts out 55,000 lumens, so that meter wont work. If u've been using the bulb for a year now regularly, it's probly time to get a new one before the one u got takes a shit.
 

Brick Top

New Member
Lights will degrade with use. Depending on how many hours of use they get per year it is wise to replace them every year. They not only lose intensity but the light spectrum, which is of great importance to a growing a healthy vibrant plant, will degrade and while the light will still seem bright and may even still read high on a meter the spectrum it puts off will not be what it used to be so replace your bulbs no less than once a year unless you are a very infrequent grower and slightly more often if you grow one crop after another all year and burn them daily all year. It is worth the cost.
 

Law03

Active Member
Over time the bulb is going to become less and less efficient. I'm sure the exact numbers differ from brand, but I would imagine that after a year it may not be running at 100%.

if your bulb isn't as bright as it used to be it may be time to get another. plus whats the worst case? you screw the new bulb in to see it was only your eyes playing tricks and a broken lumen meter, well then you have a backup bulb.

Never bad to have a backup bulb

-law
 

gubblebum

Well-Known Member
I think its due to my cooltube tbh. Just checked and its got quite the dust buildup! I actually cant believe how dusty it is till i ran my finger on the inside!! They have like 10% light reduction as it is and with all that dust ive probably been losing double that at least :( Ah well lesson to be learned, keep your cooltube as clean as possible!!
 

Brick Top

New Member
man! Ive also just found this http://i44.tinypic.com/2j0cyvn.gif

Ive always thought the recommended light distance was to the tops off your plants! So is this chart correct? As in I can actually have my buds real close as long as the leaves are 12 inches back?

If you have enough ventilation yes. If you have a light with glass that draws air through the light taking away heated air or a light like a Cool Tube you can have your lights pretty close to your plant tops but if not and if you don’t have a super exhaust system that draws cool air in low down drawing it up and through your plants and taking all heated air out through a high exhaust then you cannot have your lights as close.

It all depends on your setup.
 

LAX Skunky BwS

Well-Known Member
If you have enough ventilation yes. If you have a light with glass that draws air through the light taking away heated air or a light like a Cool Tube you can have your lights pretty close to your plant tops but if not and if you don’t have a super exhaust system that draws cool air in low down drawing it up and through your plants and taking all heated air out through a high exhaust then you cannot have your lights as close.

It all depends on your setup.


yea what dude said other wise it's 30 inches from your plants
 

richjames

Well-Known Member
30in is way too far away for a 400. Manufacture's reccommend 12-15 in exactly like in the link gubble. Personally, I only do three or so plants at a time, so I stick em all 6in from the glass on my hood.
 
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