T6's V T8's

[russellbrooke]

I've just bought a t6 bulb from aquaessentials for my jewul260 vision (along with the a brushing set so it's water tight http/www.aquaessentials.co.uk/index.php?...roducts_id=208).

Just wondered if anyone else has used t6's and any comments on your experiences with them, good, bad etc. I've only ever used t8's.

Ta

Russ

 

[Squid]

It says that it delivers more output power (watts).. about 40%

I don't quite get it though, as the 36" T6 provides 30W.. but i thought a T8 3g" tube provided 30W?

any ideas??

I would like feedback too russ.. as i have a juwel tank too..

Squid

 

[Miss Wiggle]

I would like feedback too russ.. as i have a juwel tank too..

Squid

me 3

 

[Underwurlde]

Remember boys and girls, power is NOT a rating of how much light is actually coming out of the tubes.
This is measured in lumens.
Your 30W loud speakers don't produce much light, do they (Christ now I've confused everyone).
Efficiency of the tube relates power to lumens, but this is not given. Lumens is (sometimes).

e.g. You have 2 30W bulbs. One gives out 6,500K, the other 7,500K. One is obviously more brighter (more efficent) than the other.

This is why the Watts per US Gallon rule is pretty crap. Also the W/G rule does not take into account the physical size (or footprint) of the tank.

Andy

PS
The T number is the diameter of the tube in eighths on an inch. Therefore T8 = 1 inch diameter tube.

 

[GordonTGopher]

Your 30W loud speakers don't produce much light, do they (Christ now I've confused everyone).
Efficiency of the tube relates power to lumens, but this is not given. Lumens is (sometimes).

e.g. You have 2 30W bulbs. One gives out 6,500K, the other 7,500K. One is obviously more brighter (more efficent) than the other.


Andy

PS
The T number is the diameter of the tube in eighths on an inch. Therefore T8 = 1 inch diameter tube.

I hate to question the expert, as I'm only just figuring out lighting for my tank, but I thought I understood that 'k' was a unit of colour temp and 'lux' was lumens/m2. Either I've got it wrong (most likely) or I've opened a can of worms by mentioning colour temp

Gordon
(edit: to clarify text)

 

[Waterloo Kid]

I'll go with the gopher on this one. I think it's a case of a typing error.

WK

 

[russellbrooke]

i'm a bit concerned now! I think my t8's i use are around 6500k. The new bulb i bought is 11000k (http/www.aquaessentials.co.uk/index.php?main_page=product_info&products_id=203).

Is the k reading just differences in light colour (from reading the pinned thread from George i think it is)? Does a higher k mean more light, or is that noted in lumens?

Oh, and does that mean t5 40w are better than t6 40w which are better than t8 40w?

Russ

 

[Squid]

Remember boys and girls, power is NOT a rating of how much light is actually coming out of the tubes.
This is measured in lumens.
Your 30W loud speakers don't produce much light, do they (Christ now I've confused everyone).
Efficiency of the tube relates power to lumens, but this is not given. Lumens is (sometimes).

e.g. You have 2 30W bulbs. One gives out 6,500K, the other 7,500K. One is obviously more brighter (more efficent) than the other.

This is why the Watts per US Gallon rule is pretty crap. Also the W/G rule does not take into account the physical size (or footprint) of the tank.

Andy

PS
The T number is the diameter of the tube in eighths on an inch. Therefore T8 = 1 inch diameter tube.

I know what your saying, but my 60 watt bulb in the hallway at home are brighter than my 40 watt bulbs elsewhere!

Squid

 

[Underwurlde]

oops.

Lumens, damn you all. LUMENS...

See what happens when Andy gets taken down the pub for lunch time drinkies by one of his salesmen!!!

(I only had a pint of 69er and now all I want to do is ZZZZZZZzzzzzzzzzzz).

Andy

PS
I'm not going to expand on K until I get home and SOBER UP a bit!!!!

 

[JamesC]

The power rating on a tube, ie 30W, is how much electricity the tube draws - nothing to do with how bright the light is, but there normally is some correlation between the two. The K, or Kelvin, is the colour of the tube and has nothing to do with how bright it is, but saying that our eyes are most sensitive around the 6500K area so tubes of this colour rating will appear the brightest.

Now which is brighter a T5 or T8 of the same wattage? Depends what we mean regarding brightness, intensity or overall light output? T5 tubes have a smaller diameter which means that there is a smaller surface area. This means that the 30W of power is now coming from a smaller area so will appear brighter - more intense. But is the overall light output any different from a T8 tube? - maybe or maybe not, I' don't know. Modern phosphor technology has come a long way and even modern T8's can be pretty bright compared to what they were a few years ago.

Now we come to the WPG (Watt per gallon) rule. Is it still viable with T5's. Again this depends on the overall light output from the T5 compared to a T8 or T12. If the overall light outputs are not that different then yes the rule is still valid. If you believe what the manufacturers claim then it isn't valid. I think they claim that T5's are 1.6 times brighter than T8's - but is this calculated on per square centimeter or overall output? Be interesting to see some independent tests done, if they haven't already that is.

Because of T5's intensity they are better at cutting through the water which is why they are recommended for deep tanks.

Hope that makes some sense
James

 

[SuperColey1]

Now which is brighter a T5 or T8 of the same wattage? Depends what we mean regarding brightness, intensity or overall light output? T5 tubes have a smaller diameter which means that there is a smaller surface area. This means that the 30W of power is now coming from a smaller area so will appear brighter - more intense. But is the overall light output any different from a T8 tube? - maybe or maybe not, I' don't know. Modern phosphor technology has come a long way and even modern T8's can be pretty bright compared to what they were a few years ago.

Now we come to the WPG (Watt per gallon) rule. Is it still viable with T5's. Again this depends on the overall light output from the T5 compared to a T8 or T12. If the overall light outputs are not that different then yes the rule is still valid. If you believe what the manufacturers claim then it isn't valid. I think they claim that T5's are 1.6 times brighter than T8's - but is this calculated on per square centimeter or overall output? Be interesting to see some independent tests done, if they haven't already that is.

Because of T5's intensity they are better at cutting through the water which is why they are recommended for deep tanks.

Hope that makes some sense
James

I read on another site which I linked from a link from another link in a topic in the planted section, where there was a really long experts view on lighting and he was saying that a 30WT5 v 30WT8 v 30WT10 were different because:

Same Make and brand of bulb, but the thinner the bulb the more light that can be reflected and not hit the bulb on the way back therefore if you have a T5 bulb, when it reflects from your reflector, less of the light will be blocked by the bulb on its return from the reflector whereas if you have a T10, then a lot of light will be blocked on its return. Makes sense to me, but can't vouch for the reliability of the info as I am not a scientist.

I don't think you can say wether a 30W T5 is better than a 30W T8, I'd suggest if they were the same model and make then yes the T5 should be better, but if you were rating an Interpet T8 Daylight against a Hagen Sunglo T5. Who knows which would win.

 

[JamesC]

Same Make and brand of bulb, but the thinner the bulb the more light that can be reflected and not hit the bulb on the way back therefore if you have a T5 bulb, when it reflects from your reflector, less of the light will be blocked by the bulb on its return from the reflector whereas if you have a T10, then a lot of light will be blocked on its return. Makes sense to me, but can't vouch for the reliability of the info as I am not a scientist.

This is very true and does make a difference.

I don't think you can say wether a 30W T5 is better than a 30W T8, I'd suggest if they were the same model and make then yes the T5 should be better, but if you were rating an Interpet T8 Daylight against a Hagen Sunglo T5. Who knows which would win.

Exactly, who knows. Would love to see some proper tests done on comparing T5's, T8's, etc

James

 

[russellbrooke]

and t6's!

 

[JamesC]

and t6's!

They are between T5 and T8

James

 

[nry]

I have a Realux Daylight T6 in place of my original Juwel 15watt 18" T8. I can't say it as particularly 'brighter' than an 18" Interpet Daylight Plus T8 that I also tried, but I did get an algae sppike from the T6 that was only cured by dropping the lighting period from 10hrs to 7.5hrs. Plants are certainly doing well and both the Interpet T8 and Realux T6 are much much better than the Juwel tube supplied with the tank: they are brighter to the eye in this respect.