8000k lighting

[mr. bojangsjang]

Although 6700k seems to be the standard for planted tanks (may it be FW or SW) I saw that the famous Amano uses 8000k MH lighting for his planted tanks, and after a little research it seems to be that 8000k is indeed best for flora, (freshwater at least). So, is 8000k ideal for seagrass and macros?

 

[slowECUdiver]

dunno--might be one for the people with multiple systems to test...samala, i'm looking your way

i've been having good luck with my macros under 6500k spiral PC bulbs set around a coralife 50/50 PC bulb in my nano tank. (using a bathroom light fixture to power the bulbs). very cheap approach to lighting, but even my zoanthids in the nano tank are doing well and showing growth. if there was a 8000k spiral PC bulb on the market, i'd surely give it a try...

 

[Samala]

Well, the common recommendation you're seeing for 6700K comes from my bias as a reefer unfortunately and is also an artifact of the availability of bulbs.

7189K light may be the most amazingly optimal light for plants ever, but we dont have bulbs in that precise range! I used 6700K initially because, coming from more freshwater experience than salt, it looked the most natural to me. The next bulb that is most commonly available going upwards in kelvin is 10,000K, which is fine for plants... not quite as strong for PAR ratings I understand.

The lower kelvin ratings are even too yellow for me, so you wont see me suggesting them, even though I'm sure they'll grow plants if you use something in the 4000 - 6000K range. If you can find 8000K, or something close, please let us know and perhaps a few of us can give them a shot. I imagine they will work just fine with the plants.

I've used both 10,000K and 6700 / 6500K with no appreciable differences other than, "gee that tank with the 10kK's looks cleaner..." Light is important (of course!) but I dont know that we're ready to really plunge into debates on what is the most crucial range or not, and if we should have moonlights, actinics, etc. Someday I hope we get there.

>Sarah

 

[mr. bojangsjang]

I dont know where Amano gets his 8000K bulbs, probably custom made.

Im a newb so dont laugh at this, but heres my reasoning. If you take a 4 light t5 fixture and used 3 bulbs at 67K and 1 bulb at 10K you would get something close to 8K because 67k(3) +10k= 30100 divided by 4= 7520.

Is my reasoning right? (gets laughed at but all at RC)

 

[graveyardworm]

Not laughing here, I've been pondering the same question. I just ordered my new T5 fixture for my seagrass/lagoon tank. Its a 6 foot fixture with 8 3 foot bulbs. So there's alot of possible bulb combos. My thoughts were to use 2 5K, 4 10K, and 2 actinic. I have no idea how this is going to look.

I think what you end up with is alot overlap in the spectrum with peaks at specific points in the spectrum.

 

[graveyardworm]

Im a newb so dont laugh at this, but heres my reasoning. If you take a 4 light t5 fixture and used 3 bulbs at 67K and 1 bulb at 10K you would get something close to 8K because 67k(3) +10k= 30100 divided by 4= 7520.

I see your reasoning' but I dont think it works that way. Your not going to have peak in the spectrum at 7520. Your going to have peaks at 6700 and 10k. Plants I think see light alot differently from us. So our eyes will blend the colors into say 7520. But for the plants the useable 7520 would still be lower than the 6700 and 10k. Just my opinion hopefully someone with more knowledge about light than me can add more light to your question.

 

[moosejac]

I run a 10 K bulb, because at the time of setting up my aquarium, I couldn't find any 6.5/6.7 K 150 watt HQI's to work with the fixture I already had. I have had good growth from the 10 K, especially recently, but I have found a 6.7 K bulb, and will be switching to that eventually.

 

[mr. bojangsjang]

Thanks graveyard.

Mooseejac, will you keep us updated when you make the change?

 

[jmanrow]

<a href=showthread.php?s=&postid=8091092#post8091092 target=_blank>Originally posted</a> by mr. bojangsjang
I dont know where Amano gets his 8000K bulbs, probably custom made.

Im a newb so dont laugh at this, but heres my reasoning. If you take a 4 light t5 fixture and used 3 bulbs at 67K and 1 bulb at 10K you would get something close to 8K because 67k(3) +10k= 30100 divided by 4= 7520.

Is my reasoning right? (gets laughed at but all at RC)

Hey all -
Takashi Amano uses the NA-Lamp http://www.aquariumproductswholesale.com/cart.php?m=product_detail&p=1413
on his awesome aquascaped freshwater tanks. They are 8000k.
I have not purchased from the site I posted, but do a search for "NA-Lamp", & you will no doubt find other distributors.

 

[jmanrow]

As far as I can tell, the only NA-Lamps 8000k bulbs sold in the USA are MH and PC.

I did some more searching and founf that All-Glass also makes a 8000k fluorescent! According to the spectrum graph, they peak at around 540nm, the same as the NA Lamps. The price is much cheaper too!
http://www.drsfostersmith.com/produ...tCom-_-Fish-_-48 All-Glass Fluorescent Bulbs (32W)&ref=3554&subref=AA&GCID=C12188x006&ctt=64

If these are the bulbs that I think they are, they have a really nice color rendition, and there should be no need for supplimental actinics.

 

[mr. bojangsjang]

Thanks jmanrow!