But anything in the range of 4100k to 6500k would be good IMHO, During the day, natural sun light goes through this range with 5000k being "noon"
Some research suggest that a mix of 3000k and 6500k basically equals 4100k
All depends on the source of the data, what you to watch out for is broad claims, different bulbs with different phosphors, different CRI's, tri or halo phosphor etc etc etc will have different characteristics
statements like "Get 6500k, or get 5000k"... is like saying get a chevy or ford, but without the model or year... you really dont know exactly what you are getting... but it will probably get ya home.
I like to use spectrometers, here are my bulbs
sorry for the crappy image quality, shot those freehand just now...so meh
As you can see these are classic tri-phosphors (the 85cri also gives that away)
Im getting primary spikes at
435nm, 545nm and 610nm with secondary wavelengths primarily in the reds and blues
across the pond you can get the triphosphor sylvania gro-lux in 54w T5, now that would be the bomb!!!!!! they have a beautiful spectra
(Ive emailed sylvania more then once..... waiting patiently LOL)
Spectrometers are cool and you can roll youre own using a cdrom and cereal box
I usually search for "t5 54w" and include descriptions in the search params
oh and here is the one i was thinking of
RL7836: they are 3 foot long or 36 inches.
“Experience: that most brutal of teachers. But you learn, my God do you learn.” C.S. Lewis
I have both the 4 bulb and 6 bulb fixtures
The 4 bulb isnt in use at the moment
as far as bulbs go, that is what this whole thread has been about...the majority of research has been done by the freshwater planted aquarium hobbyist.
It is commonly accepted that the GE starcoat is the best "standard" bulb availabe to the USA market. There are specialty bulbs out there, ranging from good to bad...
Usually if you will google the bulb name and the word photosynthesis in the same search you will get some hits
Not really a black and white answer but.... stay with a major brand, stay with 4100k-6500k and you will be ok
In the future look for more options to become available as the T5 becomes more widely accepted.
It is a great format that will be king till they eventually get replaced by economical wide spectrum white LED's (guessing 5-10 yrs away)
I have found everything I want. Would 4 T5 HO 54W bulds with a CIR of 85 and a rating of 6500k and producing 5000 lumens be sufficient for h/l neps and helis? Or do I need to aim for the 6 bulbs? What distance would you advise the plants be from the lights?
I would advise perusing the last month or 2 of T-5 threads (or longer). One of the issues with T-5's (not yet mentioned in this thread) is their heat generation. Depending on your enclosure design, multi-lamp T-5 fixtures & highland Neps may not play well together ...
Otoh - for a petiolaris tank ...
have not taken the plunge into the t5 realm but have researched some packages and other than the site av8tor1 recommends, I found this site as well - http://www.littlegreenhouse.com/accessory/lights2.shtml the sunblaze systems caught my eye