what is 6700k on light bulbs?

[jcardona1]

I like to have a firm understanding of the science behind something before i actualy do it which is why i have spent far too much time researching lighting than actualy replanting my tank.

Lighting is the easy part I say. It's also the easiest to overdo. Most folks worry too much about the lighting, then invest little time/money into co2/ferts. The only things that should concern you about lighting is wheter you're adding so much that it will give you algae problems

 

[Zander_The_RBP]

Exactly. The spectrum of actinic lights is that found in deeper water, where corals grow. Deeper water contains a more blue spectrum because the red/yellow spectrum gets absorbed by the water first, while the blue continues into the depths.

Freshwater plants on the other hand grow in much shallower waters, therefore they have not adapted to use the blue spectrum of actinic lights. While actinics lights may still grow freshwater plants, I believe there's two reasons why you don't see people use them:

1. It's not typical of a plant's environment in nature. We try to re-create their natural environment, so we use lighting that matches what they get in the wild.

2. Actinics looks like ass on a freshwater tank, and look like even more terrible ass on a planted tank

While it's true that they simulate deeper environments better all the light that reaches those depths are still present in shallower waters. 420nm and 460 nm light are peaks for chlorophyll-a and chlorophyll-b and will be used by plants.


If you want to simulate natural light best then your going to have to put your tank outside in sunlight because fllourescent light is hardly natural. Compare the spectral curve in sunlight, it's a perfect curve a flourescent is a jagged line. Plants will grow fine whether under natural or artificial light as long as their PAR requirements are met.

As for the comment on actinics and rear-ends.... well lets just say what looks good is an opinion not a fact and that it is up to people to choose whatever lights they like best for THEIR tank, and in the end that's what my post was saying that people need to care less about ideal colour temp and such but instead do what looks best.

Lighting is the easy part I say. It's also the easiest to overdo. Most folks worry too much about the lighting, then invest little time/money into co2/ferts. The only things that should concern you about lighting is wheter you're adding so much that it will give you algae problems

Yes i completely agree what i was trying to say in my post was that colour temp was at best a geuss of the value your light source has to plants. Intensity(or lack thereof) should be the top concern.

Decide on what lighting you are running and everything else will fall into place Lighting determines how much co2 and ferts you will need.

Beleive me i understand that nowhere in fish keeping is any technical knowhow required (including Co2 and ferts) and especialy lighting i was trying to bust some myths surrounding colour temperature.

In conclusion: Spend less on fancy colour temps designed for plant growth go out and buy some decent fertilizers for God's sake.

 

['vspec']

Not bad for a Canadian!! Thank you for taking the time to share your research findings.

Lighting is a complicated beast at the best of times, & as more research uncovers various aspects, it compounds it.
Judging by that, I'm surprised its usable in the actinic spectrum, however those graphs, even through flashy in implication, id like to see the tests first hand thats for sure.

On that note of assumed correctness, i retract my previous statements.
Im still sticking to my guns on quality duty cycles though, seen this first hand on the hydroponic scene. Quality ballasts reduce cycle timeframes - filling the gaps and producing more light within its own 'on' cycle.

 

[splant]

Looks like ass and is considered by experienced planted tank folks to be useless... that's why I have 4 54 watt t5ho actinic bulbs and 2 65 watt actinic PC bulbs in my garage. I switched out the actinics that came with the fixtures for 6700k since that's what is commonly recommended.

RBP You may be onto something new and if it works for you that's awesome but for someone just starting with plants I'd say stay away from actinic bulbs.

A combo of actinic and 10,000k does look good on my African cichlid tank but I actually just switched it out for a 6,700k too. I personally can't deal with a tank with no plants lol

 

[Zander_The_RBP]

[QUOTE='vspec';450613;1]Not bad for a Canadian!! Thank you for taking the time to share your research findings.

Lighting is a complicated beast at the best of times, & as more research uncovers various aspects, it compounds it.
Judging by that, I'm surprised its usable in the actinic spectrum, however those graphs, even through flashy in implication, id like to see the tests first hand thats for sure.

On that note of assumed correctness, i retract my previous statements.
Im still sticking to my guns on quality duty cycles though, seen this first hand on the hydroponic scene. Quality ballasts reduce cycle timeframes - filling the gaps and producing more light within its own 'on' cycle.[/QUOTE]

Not nessicarily more light but more productive light for sure. A 54 watt flourescent will draw an avarage of 54 watts. This is from cycling on/off from 0 to a much higher wattage. Good ballasts will cycle on/off to a much lower wattage but stay on longer, and because plants can't turn off photosynthesis while the light is off this is much more productive than more off time. I agree 100%.


I agree on tests what i would really like to see someone try is compare the PAR from an actinic tube against one of the same wattage "full spectrum" tube. If anyone has a PAR meter and an actinic tube on hand and tries this please send me a PM im very intrested to see the results.

It should be noted that flourescent tubes CANNOT be monochromatic; they can't give off only 1 wavelength of light they merely peak in and around 460nm (on a 460 nm actinic tube) or 420nm (on a 420 nm actinic tube) and give off miniscule amounts of other light.