Lighting Suggestions Needed

[froggsong]

different "colors" of light affect plants in different ways. From what I understand, redder light makes plants grow stronger, and I think it is good for budding (please correct me if I'm wrong, this isn't my best subject yet, lol). Green light is somewhat useless, because plants reflect most of the green light (that's why most plants are green), though I have heard that green light speeds germination.

A mix of a "grow light" (you know, the pink ones, lol) and a "daylight" bulb might be the best choice.

After doing a little more reading on the subject, I came across this great article: Indoor Plant Lighting. Please read through it, it contains a wealth of information. This is one of the best write-ups I have seen on the subject.

[Epiphile]

I wouldn't claim to be an expert, either, but I think that the jury may still be out on the whole colour temperature thing and how it affects different plant processes- you could read the argument for days and days if you felt like it.

I personally use lamps between 5000 and 6700k because I like that light best, and as far as I can tell it hasn't really affected flowering. If you've got a full spectrum it shouldn't be a big deal, because after all what you're trying to do is deliver usable light that falls within the range of the photosynthetically active.

[MtuPup]

Great article.

I'm going to go with a dual T8 light - based mostly on pricing and availability.
I think if I was dealing with a taller tank I'd be a lot more inclined to go the T5 route.

I've also obtained reference material used in my office for Energy Management Systems and there is a great section on difference between T5, 8, 10, 12 lighting and goes into detailing what the CRI and Lumens actually mean as well as the equations to figure out how much light is actually getting into a space.

T5 would be a lot brighter but coupled with the article on plant growing might be overkill.

[beckdg]

no, pink light is not necessarily the enemy. from what i see on the fish/plant bulbs the spectrum has 2 immense peaks. i think that might be part of the culprit but those bulbs are just crap. it's a quality thing in this case as far as i'm concerned.

3000k (viewable as red or pink i believe) is the flowering spectrum. around 6500k-6700k is the area for growing... one could go past either end of this spectrum and it could be debated all day but it seems to work best for most. if you were to do a night light 4100k simulates the moon but would still have to be dim so as not to disturb animals or your lighting cycle.

full spectrum light is best all around as it seems everything does better with light closer to that of the sun that provides colors across the spectrum. many 6500-6700 bulbs happen to be full spectrum usually so not only do you get a range of colors that support photosynthesis but the main color is also photosynthetic and good for growing. the ge chroma 50 (ge daylight fluorescent) is a good example of that and is often suggested for those that go t-8. it is not your only option though.

one thing to take into account is that green light for the most part does not support photosynthesis as like froggsong mentioned the green is absorbed or reflected (i forget which). just as well it has been said that some herps (especially reptiles) cannot see red light... hence why they use them for night lights for herps.

another thing to take into account is bulb ratio. a few articles i've come across in the past (especially relating to hydroponics) have suggested that a ratio of 2 or 3 bulbs in the growing spectrum to 1 bulb in the budding spectrum produces the best lush growth as well as promoting budding and flowering pretty well. this can be accomplished simply by adding a smaller bulb for budding at the right time of season or permanently. you don't necessarily have to have 3 or 4 bulbs... go by lumens and figure 3 to 1 and you should be fine.

also lumens has something to do with light output viewable by the human eye. if you really wanted to get a good reading of what the plants see or can use it's best to use par. i think it's photosynthetically active radiation. par meters should run about $100, maybe less as i've only priced waterproof ones. then as if that isn't enough you have lux... but that's not necessary i don't think.

moral of the story is if you were to go with just 6500-6700k bulbs you'd more than likely be completely fine. if you were to mix and match i believe knowing and using the ratios above would help alot.

in conclusion hewe really is the plant expert and we should probably wait for him to let one of us know how really ridiculous we sound... lol.

[MtuPup]

I feel like there should be a college course offered on this.

[beckdg]

you're telling me. i can't believe i'm still learning. i'm on a couple fish forums too and these guys hit it from all angles. when i was in school i thought i'd never use chemistry again but with 2 planted tanks it seems i'll never finish chemistry and lighting alone. i'll probably be doing a reef tank in a year or 3 when i feel i'm ready. i have noone near to learn from and i refuse to kill them guys... i'd be broke for life in a matter of weeks.

anyway basically 2 bulbs, full length of the tank, 6500k-6700k and you should be good. you can get one at any hardware, gardening, hydroponics and some other stores most of the time. usually you have to turn the package to check the spectrum or pull the bulb end out of the sleeve and see if it's on there. you can usually check on line also if you can get the bulb type or number and who manufactures it.

[HewesHort]

you've just about said it beck i will add there is a formula out there for converting f-stop read by a camera in to par, ill see if i can dig it up.

the thing about using the extra red light is that it only needed if you are trying to grow plants for their flowers, ie orchids or pot most of the plants in our vivs are foliage plants so we dont worry about them flowering well, thats not what they are grown for. the extra light wont hurt but isnt all that necessary.

Ahhh... hydro stores, i have stood there for hours arguing with the sales people over everything from the causes of root rot to whether or not foliar feeding causes spider mites. keep in mind a lot of the employees have experience growing only one type of plant, weed. most of them learned to grow from a friend and have no clue about how plants grow, they just know that cuttings + ferts = $$$. that is not to say that all hydro store workers a idiots, some of the best horticulturists ive ever met work at hydro stores. im just saying that they arent used to people coming in looking for something other than growing equipment.

Wiring leds is quite simple, if you know a bit about electronics. i can post some links to some good info if you like.

[beckdg]

1 i'll bookmark them if you post them
2 f-stop, REALLY? i gotta see this!
3 HewesHort; "Ahhh... hydro stores"... my sentiments exactly
4 da_n it, i forgot nanometers

[beckdg]

i just came across this... been reading for a while for a brush up.

it's like the full unabridged idiots version of aquarium lighting cliffs notes.... Aquarium Lighting; Kelvin, Nanometers, PAR, Bulb, Watt, MH, LED, light basics.

figured when one of us were bored there's something else to fry our brains.

[Epiphile]

Originally Posted by HewesHort

...i will add there is a formula out there for converting f-stop read by a camera in to par, ill see if i can dig it up.

Are you sure it's not foot-candles that you can glean from a camera's f-stop? I could be wrong.

And is anyone able to point me in the direction of some text that explains how and why different colour temperatures of light affect different aspects of plant growth? I'm not so sure that I buy it.