anyone prefer FL over PL lights ?

[dx]

I would like to hear the comment of people who prefer FL over PL lights.

I have been using PL lights, due to its higher wattage and presumed longer lasting. I have DIY Osram 36W, CR (Coral Reef) 55W 2ft and CR 2 x 24W 3ft. Find that CR 55W became dim faster.

For FL lights, I believe the spectrum have to be at red and blue color wavelengths, but not sure the implication of "K", e.g. 7000K. Is that related to intensity ?

In the market, there are so many brands of FL lights and so much price differences. Bioplast product can cost more than $30 for 15 W tube and Aqualux cost about $10.

What is the spec. I should look at for FL tube ? (By the way, do they have spectrum control for PL lights?)

Again, if I want to grow Glosso or hair grass (just the foreground part) in 2 ft or 3 ft tanks, anyone could recommend the combination of FL lightings ?

[Aeon]

To grow glosso right, you need more than 3W/USG and CO2 @ 20-30ppm.
For a regular 60.7x30x49mm tank, you'll need more than 70W to achive that so that's about 5 15W FL tubes. Maybe you can DIY or custom made. commercial available FL fixtures usually allows up 2 tubes per fixture and you only have enough space for 2 fixtures. only 60W which is not quite enough.

PL is what I use now, the compactness is really a plus. problem is I cannot find PL tubes which are as good as my old Biolux FL tubes.

K degrees is the indication of color temperature, imagine what color an extremely heated iron will glow in at a certain temperature. blue is hotter than red flames. the sun is roughly 6500k (daylight tubes), it has nothing to do with what spectrums of light it produces.

My personal preferences are 7000+K Triphosphor tubes with a CRI of more than 74 which I think is beneficial to both plant grow and natural-looking colors of plants and fish.

[crandf]

Surely color temperature has everything to do with spectrum. I think the combined frequencies produce a final color that is rated with K units. There's probably some empirical equation for this.

Its arguable how much FL light is truly needed. I have a 60x30x45 tank with 2x15 watt Mozoo FL plant lights, where I have glosso growing. Initially they grew to about 8cm tall, but recently they started to spread horizontally yet still remained short. CO2 injection was by diy and was quite haphazard, and these few weeks I stopped CO2 injection altogether. CO2 levels now should be about slightly lesser than 3ppm, since I'm using a hangon filter that produces a moderate surface turbulence.

[vinz]

Crandf,

Why do you think its slightly below 3ppm? I'm trying to figure out which direction your coming from? That the surface agitation is keeping the CO2 at ambient or that its depleting the CO2?

Actually, there's a thread on the APD about glosso and light some weeks back. Seems you don't really need "high" light to grow them well. Starts here . The topic title changes and sometimes the thread does not auto-link properly, so do some digging in here and the following months.

[crandf]

Vinz, its the first reason.

[dx]

[quote:3b284a4273="Aeon"]

PL is what I use now, the compactness is really a plus. problem is I cannot find PL tubes which are as good as my old Biolux FL tubes.

K degrees is the indication of color temperature, imagine what color an extremely heated iron will glow in at a certain temperature. blue is hotter than red flames. the sun is roughly 6500k (daylight tubes), it has nothing to do with what spectrums of light it produces.

My personal preferences are 7000+K Triphosphor tubes with a CRI of more than 74 which I think is beneficial to both plant grow and natural-looking colors of plants and fish.[/quote:3b284a4273]

Aeon, the FL tube packing usually printed K value and the spectrum showing which are the strong colors. Say I choose one with 7000K, do i have to bother about the spectrum ?

And also, you said you can't find a PL light as good as Biolux FL. What are the good points you are referring to ?

For glosso, I think it is a rather controversial, people have say not necessary high light / CO2. Maybe the thickness of the gravel also plays a part as how easy the glosso can get the base fertilizer. And perhaps the gene of the glosso ? Glosso needs to be trained to creep.

[Aeon]

Here's some good lighting information, detailed explanation of what's K, CRI, etc...

http://www.geocities.com/CapeCanaver...lighting1.html

[dx]

looks like there isn't many FL tube fans here and Osram PL tube 36W can be easily get and cheap (~$10).
Then, I really wonder who will buy those expensive FL tubes from Arcadia, Sera, Bioplast ???