T5 lighting...

[SilverDollarMan]

Ive been doing some research on T5 systems and have read somewhere that the wattage per gallon rule doesnt apply for T5's. Is this true?


I currently only have 1 20 watt bulb at 6700k.

But since my tank is a 29g, I could only fit a single tube T5 fixture, the doubles only come in larger sizes.

 

[customdrum]

wpg rule on t5 ? never herd of that since t-5 ho is the best lighting for the money.
t-5 high output is brighter than a normal t5 but about the same wpg really.
1- 20w t5 over a 29g gives you maybe 0.5 wpg. if you have low light plants like, java fern, anubias,java moss, anarchis, maybe crypt wendtii they shouldnt die but wont grow much.

 

[SilverDollarMan]

T5's dont come in 20w
they come in 24w

but since they are high output they supposedly dont require the wpg rule and all that matters is the color temperature/kelvin.

Just wanted to know if this is true.


also, in my origonal post i ment that I have only 1 20w bulb, that bulb is a T8.

 

[phanmc]

The wpg rule still applies but you should aim for the lower estimates when using T5HOs. So the 24w T5HO is still quite low for a 29g tank, should be enough for the hardier low light plants like java ferns, crypts, and anubias but not much else.

Color temps matters little in terms of plant growth.

 

[DSR]

Color temps matters little in terms of plant growth.

Not to question the above quote, but I believe the color temp does matter, quite a bit. The color spectrum, as related to the kelvin scale, relates directly to the growth of plants. For example, a 6700K lamp with Xwatts will provide more beneficial lighting than a 14000k lamp of equal wattage because the color temp/spectrum is correct for plant growth.

That is just my understanding and perhaps I am missing something...

 

[phanmc]

Not to question the above quote, but I believe the color temp does matter, quite a bit. The color spectrum, as related to the kelvin scale, relates directly to the growth of plants. For example, a 6700K lamp with Xwatts will provide more beneficial lighting than a 14000k lamp of equal wattage because the color temp/spectrum is correct for plant growth.

That is just my understanding and perhaps I am missing something...

The Color temp is not the same thing as the color spectrum output, that curvy or chart that some manufacturers provide. The color temp simply means that the color emitted by a light source looks like the color of a black body when heated to a certain kelvin temperature. Since different manufacturers uses different materials to achieve that color, the spectrum chart can vary greatly from light sources with the same color temp.

Color temp is not a reliable indication of PAR (photosynthetically active radiation) which covers the beneficial light output for plants.