Light Penetration

[Themuleous]

Simple question, if you have the same wattage of light say 100w from one bulb (yes I know its probably not technically possible, especially from T8's but stick with me) all producing the same wavelengths and having the same Kelvin rating, is there any difference?

I have heard several people ask if T5's have more penetration power than T8's, it is true? And if it is why when for all intense and purposes they produce the same light? Surely light of the same wavelength, same wattage, same Kelvin is the SAME?

Cheers

Sam

 

[oldwhitewood]

You are missing out the component of light output, luminens. T5s are meant to have a higher output in luminens than T8.

Kelvin is to do with colour temperature really, this changes apparently. For example the 6500k is meant to be daylight, they reckon the Kelvin at a depth where aquatic plants would commonly grow underwater changes to 8000k.

 

[Themuleous]

I hadn't considered that you're right, would that explain it then?

Just so everyone knows lumens are defined as the following -

a unit of luminous flux equal to the amount of light given out through a solid angle of 1 steradian by a point source of 1 candela intensity radiating uniformly in all directions

But just so you know

 

[oldwhitewood]

I was just about to say that very thng Yeah come on everybody get with it!

 

[Themuleous]

I think Ive worked it out, so even if the wattage is the same, T5 tubes are able to convert more of that wattage into light i.e. produce more lumens/candel power? The light is therefore more intestes so penetrates better? But I thought the penetration was dependent on the wavelenght of the light?

If Im being stupid just tell me to shut up, but if there is a valid reason (other than their size) for using T5's then maybe I should upgrade.

 

[oldwhitewood]

I think it is as you have said but to be honest I am not 100% on this, we need an expert on lighting to advise us. I am sure it is to do with power in luminens and the smaller tube being more efficient. I think when I mailed arcadia they said one T5 roughly equates to 2x T8 of the same wattage but this could be absolute claptrap!

 

[Themuleous]

Haha cheers for the advice all the same.

 

[plantropimunity]

check out the lighting forum over at reefcentral.com for several threads regarding the differences between every kind of lighting. if i can figure out how to post a link, i will do so.http/reefcentral.com/forums/showthread.php?s=&threadid=741281
i think that is the one. hope it worked.

 

[fozzy_wozzy_woo]

How deep are you looking at going?

if it is deeper than 1.10M then dont bother as any lighting will not penitrate the depths. when i say this the goodness of the lights will not penitrate the depths even though it looks like it does.

sun light only penitrates to about 2.5m so any thing below this must be able to live on minimal amount of light

 

[Themuleous]

This is more of a hypothetical question, just out of curiosity. As I said if T5 light is better at getting to the plants then perphaps I should upgrade?

 

[fozzy_wozzy_woo]

This is more of a hypothetical question, just out of curiosity. As I said if T5 light is better at getting to the plants then perphaps I should upgrade?

Make sure to check the web to see if your fish has a reaction to t5 lighting.

I know of a few fish that dont like t5 and they just die.

 

[Themuleous]

Oh blimey, I didnt know that, I sure will check!

 

[oldwhitewood]

Never heard of that myself! Are we talking the blind cave fish here? You'd think it wouldn't be bothered.

 

[Andyg]

Hi,

The benefits of T5 tubes in comparison to T8's are the intensity of the light that is produced.Watt for Watt they have greater intensity. Like all aquarium lighting, these benifits are only really utilised when fitted with the correct reflecters.

The most intensive T5 I have found so far is the D&D Aquaplus blue. Most people would think this tube to be best suited for marine applications.Not so. Try one focussed on the fore ground of the tank and watch your riccia,HC and Glosso grow and pearl like never before. I have tried several brands and combinations and would never be without one of these tubes at the front. The colours of the fish look incredible also, especially Cardinals and Rams.

Kind regards,

Andy Gardner

 

[MoreCoffee]

Simple question, if you have the same wattage of light say 100w from one bulb (yes I know its probably not technically possible, especially from T8's but stick with me) all producing the same wavelengths and having the same Kelvin rating, is there any difference?

I have heard several people ask if T5's have more penetration power than T8's, it is true? And if it is why when for all intense and purposes they produce the same light? Surely light of the same wavelength, same wattage, same Kelvin is the SAME?

Cheers

Sam

A bit off your T5/T8 subject, but interesting regarding light penetraion..........
is the subject of quality of the water and depth.

A few days ago I read a thread on APC about some guy who did an experiment with a LUX meter in a 10Gal tank that had 'yellow' water (from tannins).

He recorded the reading from the LUX meter (at the bottom of the tank) during a series of water changes.
He recorded an increase in lower tank light levels of 252.94% (YES 252.94%) from the first reading to the final one.

APC link <- Should I post links to other forums ... not sure but it's done now !!

His post regarding readings at different depths in a tank also shows how depth of water impacts on penetration.


.............. Just thought it was worth dropping in !


Mr G