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Depends on what you want to grow.
hw deep can a 36W 6500K PL light penetrate thru the water??
is a height of 2ft too tall/high for the rays of a PL light to penetrate?
if so,whats the recommended height..?
Depends on what you want to grow.
furry plant grower
!) Reflector design: Some disperse the light so the beam have lesser penetration, others focus the beam so you may get good penetration at one spot but poor dispersion throughout the whole tank.Originally Posted by sonique
2) Lens: (Plastic cover of your lamp) an old scratched up lens diffuses the beam. More diffusion = less depth
3) Surface agitation: higher surface agitation eg from a fan decreases penetration
4) Water clarity: clearer water gives beter light penetration
5) Distance of lightsource to reflector: greater the distance, the greater the focus and penetration. However, all the PL casings I've seen don't seem to offer much depth to enable proper focusing of the beam. You'll probably be better off with MH lamps for your 2ft depth. Alternately, the new T5 tubes with parabolic reflectors seem to offer reasonably good throw too.
Warm regards,
Lawrence Lee
brothers, whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable--if anything is excellent or praiseworthy--think about such things.
Philippians 4:8
I noticed that light-sets usually have quite a standard height for their stands. I'm using T5s and my tank height is 18inch. What is the recommemded distance from the water surface to the light source (a distance which is good for most plants)??
Is there a standard way or calculation for the distance which is good for most plants?
there are no standard. just place it at the height that is fixed by the light stand. else adjust the height to your liking.
do note that placing the light set nearer to water surface will heat up the water slightly more but offers a little more light intensity.
thomas liew
what is the size of your tank?
generally, pl or fl tubes are sufficient to grow a huge variety of plants for a 2" tall tank. just remember the guide of 2-3wpg.
thomas liew
was planning to get a 2ft cube tank...but the height of 2ft is making me wonder whether light can penetrate to the bottomest part of the tank..
if growing plants which require high light,at the bottomest part of the tank, would they get sufficient/max light??
pl should be no problem for 2" tall tank.
for plants that require high light, plan for >3wpg.
there are many aquarist who kept creeping glosso with pl lights.
thomas liew
Yup.. pl for your tank height is ok.
By the way, what are you planning to keep?
- eric
Hi sonique ,
Read this in one of the article written by a Marine guru in the net, if you're interested the whole article can be found in
http://www.arofanatics.com/forums/pr...?t=77883&pp=40
In summary of the lighting portion, it states that
Effective water penetration power of bulbs and tubes:
Fluorescents - Down to 12"
CF like PL, T4 and T5 - Down to 15"
MH 70W - Down to 16"
MH 150W - Down to 20"
MH 250W - Down to 24"
MH 400W - Down to 30"
Hope it helps.........
The article is so detailed... Wonder if planters have a similar one...
But I find that the way of using W/sq ft sounds much logical... So for planted tanks, what then would be an acceptable range in W/sq.ft?
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