6700K vs 10000K power compacts

I'm getting ready to drop some dime on my first lighting system that I didn't buy at Home Depot. That's right, after some 30 years in the aquarium hobby, I'm going to try to keep a plant alive more than a few weeks.

I've got a 55 gallon tank. It's going to be a mix of native plants and fish, deep bed like farmertodd has advocated. I'd rather not get into CO2 injection, at least not at this point.

I know 6700K is supposed to be close to ideal for plants, but given enough wattage 10000K is supposed to be more than sufficient as well.

Looking at the hardware that is out there, and my budget ($200-$250) I seem to have a few options in front of me if I go with a 4x65W system:

1) 100% 6700K bulbs (260W)
2) 100% 10000K bulbs (260W)
3) 50% 6700K / 50% 10000K (260W)

Then there is also a much cheaper option. I can go with a 2x65W system and end up with:

1) 100% 6700K bulbs (130W)
2) 100% 10000K bulbs (130W)
3) 50% 6700K / 50% 10000K (130W) - You can apparently get a single PC bulb that is 6700K down one tube and 10000K down the other

I'm a little concerned about the 4x65W route in that I've read you really need CO2 injection with that much light. To say nothing of the heat issues with a native tank!

I'm a little concerned about the 2x65W route in that it might not be enough light for the plants.

And then there is the whole 6700K vs 10000K matter... which looks best?

I normally don't fret over aquarium gear purchase like this, because I rarely have to spend this much since I've only really been concerned with the health of the fish (which are much cheaper to keep happy). So I'd like to hear some opinions from others that are doing well with plants and have experience with Power Compact lighting systems.

I've never used power compacts, but do have some thoughts about bulb color temperature. The color temperature is just a way of rating the way the light looks. Higher K is more blue looking, lower is more red/yellow looking. This is different from the spectrum that the light puts out. Unfortunately, what is really important is the spectrum.

What I do with regular fluorescent bulbs is use a mix of warm white and cool white (which would translate to a mix of high and low K). Sometimes the warm white are called "kitchen and bath" and the cool white called "daylight". This is also what was used by the botany department when I was in grad school in the plant incubators.

My opinion is that any bulb that is specifically labeled for aquarium use is way overpriced. I would take my cash and go to a lighting store where they will spend the time with you to go over the different types of bulbs. It seems that most of the bulbs sold under the aquarium trade are also available under other, less expensive names at the lighting store. Not sure if they do compact fluorescent, though. But surely worth a phone call.

Also - the bulbs sold at big box home stores labeled "plant and aquarium" are marketed as having the proper wavelength (spectrum), BUT they seem to get this way by simply sheilding out the light that is in the unused wavelengths. If you look at the amount of actual light emitted (printed on the box), it is much lower for these bulbs.

Thanks. Any thought on the 2x65W vs 4x65W configurations?

I have 15 tanks right now, all but two are planted. Most are small tanks, the largest ones are 29 gallons, which is a couple of inches shorter than your 55. I use regular 20 watt fluorescent bulbs in all of them. I get the twin-tube fluorescent fixtures from my LFS and the bulbs from Lowes or wherever. I've used a cool white plus a plant bulb as per Walstad, lately I've just been using two daylight types. I like the way those look. I don't use CO2, but I do use Seachem's Flourish Excel which is supposed to provide "organic carbon." I like the results I'm getting. I can't grow the plants that need high light levels, but I can grow swords, crypts, hygro, and anubias just fine.

I use a mix of 6700/10000 in my Tropical 75 Gallon. Mine gets hot, but there are models with built in fans I would recommend. When I switched over to these, plus CO2 my plants absolutely exploded! Soon, I will post a thread on my CO2 generator and reactor set up; inexpensive and well worth it.......check it out.

Here is the one that I'm leaning towards:
http://www.marinedep...ct~CU01006.html

48", 2x65W bulbs.

Each bulb is half 6700K white, half 10000K white.

Includes two "lunar" LED's for night lighting. cooling fans... I'm still trying to figure out whether or not it comes with the plastic brackets to stand the lamp a few inches above the top of the tank for better cooling or not. So it looks pretty complete for about $110. 130W of lighting on a 55 gallon tank... I know a lot of hardcore plant guys are going to turn their noses up at that but it should be a lot better than the 80W of cool & warm white bulbs I used to use in a cheap-o Home Depot "shop light" fixture on this tank (that combo didn't work too well for me).

EDIT: Another contender, not even Power Compact... I'm just now learning about these T5 HO bulbs:
http://www.marinedep...ng~vendor~.html

OK I closed my eyes and opened my wallet.

I ended up getting light fixtures for two native plant tanks.

My ten gallon quarantine tank will now have a 40W Power Compact light fixture. The bulb is half 6700K, half 10000K.

My 55 gallon display tank will have a 2x65W power compact light fixture. The bulbs are the same 6700K/10000K like I got for the 10 gallon, just in the bigger 65W size.

The bulbs and fixtures are all Current USA brand. The fixtures are the Satellite model.

I wish they would sell these things without bulbs, though.

I've got a couple current compact fixtures and I couldn't ask for more. Next time you buy one wait for it on ebay. Your wallet will smile at you.
Ohhhh make sure you plug in the fan for the double bulbed fixture....it's annoying, but it will get SUPER hot if you don't.

I've got a couple current compact fixtures and I couldn't ask for more. Next time you buy one wait for it on ebay. Your wallet will smile at you.
Ohhhh make sure you plug in the fan for the double bulbed fixture....it's annoying, but it will get SUPER hot if you don't.

The funny thing is, I checked eBay, and marinedepot.com was way cheaper.

130 watts on a 55g is 2.3 watts per gallon. That would be considered a medium light tank. I have 96w of t8 6500k on my 55 and can grow many plants. You shouldn't be too limited on plant choice. Make certain you plant heavily with fast growing plants initially so the fast growers can compete with the algae for nutrients. You might have some algae problems with that much light if you don't have enough plant mass.

How much did you get yours for?
I payed $49 for a 36' single and $63 for another 36' single both prices after shipping on ebay.
As opposed to the $156 drfostersmith.com got me for a 24' double last year.

Have you thought about supplementing the 6500K with some actinics? It'll look a whole lot better.

One of my bulbs is half and half and I don't care for that much blue.

I've never used power compacts, but do have some thoughts about bulb color temperature. The color temperature is just a way of rating the way the light looks. Higher K is more blue looking, lower is more red/yellow looking. This is different from the spectrum that the light puts out. Unfortunately, what is really important is the spectrum.

What I do with regular fluorescent bulbs is use a mix of warm white and cool white (which would translate to a mix of high and low K). Sometimes the warm white are called "kitchen and bath" and the cool white called "daylight". This is also what was used by the botany department when I was in grad school in the plant incubators.

My opinion is that any bulb that is specifically labeled for aquarium use is way overpriced. I would take my cash and go to a lighting store where they will spend the time with you to go over the different types of bulbs. It seems that most of the bulbs sold under the aquarium trade are also available under other, less expensive names at the lighting store. Not sure if they do compact fluorescent, though. But surely worth a phone call.

Also - the bulbs sold at big box home stores labeled "plant and aquarium" are marketed as having the proper wavelength (spectrum), BUT they seem to get this way by simply sheilding out the light that is in the unused wavelengths. If you look at the amount of actual light emitted (printed on the box), it is much lower for these bulbs.

Hmm, very interesting point you make about the reduced light on the plant&aquarium bulbs. I was about to make the same point you made on light spectrum but was going to recommend the plant&aquarium bulbs. Then I read your post and a light came on in my head.
I have been using a mix of cool white, full spectrum and plant and aquarium bulbs for years, but I've always wondered why the p&a bulbs seemed dimmer. They also lose intensity much faster. Could be because of what you say about blocking the light. Makes sense.
FWIW, my 14 year old just did a science fair project in which he grew sunflowers under cool white, full spectrum and p&a bulbs. The p&a bulbs had a slight edge over the full spectrum and both easily outshined the cool white. Plant height, number of leaves, size of leaves, plant color and overall appearance were the criteria measured. This was done with brand new bulbs and bulbs were kept 3 inches above the top leaves.
BTW, he got second place. The teacher's son got first.

The teacher's son got first.

It was rigged, we all know who's son really won.

What an awesome science project!!!!! Now.... for this year's event.... have him do aquatic plants!!!!!
I would even help provide plants if needed (assuming I have or have access to what he wants at the time).

Hmm, very interesting point you make about the reduced light on the plant&aquarium bulbs. I was about to make the same point you made on light spectrum but was going to recommend the plant&aquarium bulbs. Then I read your post and a light came on in my head.
I have been using a mix of cool white, full spectrum and plant and aquarium bulbs for years, but I've always wondered why the p&a bulbs seemed dimmer. They also lose intensity much faster. Could be because of what you say about blocking the light. Makes sense.
FWIW, my 14 year old just did a science fair project in which he grew sunflowers under cool white, full spectrum and p&a bulbs. The p&a bulbs had a slight edge over the full spectrum and both easily outshined the cool white. Plant height, number of leaves, size of leaves, plant color and overall appearance were the criteria measured. This was done with brand new bulbs and bulbs were kept 3 inches above the top leaves.
BTW, he got second place. The teacher's son got first.

What an awesome science project!!!!! Now.... for this year's event.... have him do aquatic plants!!!!!
I would even help provide plants if needed (assuming I have or have access to what he wants at the time).

Funny you should say that. We origionally planned on using some aquatic plants grown in the hair algae contaminated water from my planted tank. I was curious to see if the algae would grow better under the different spectrums and if the algae and higher plants responded differently. The whole thing started getting too complicated and finally the kid said to me, "Dad, it's MY project, not your's!" He squashed the algae component and stuck to the fast growing sunflowers.

Why has no one mentioned bulbs less than 6000K? I believe the best "plant" bulbs are going to be around 4200K.

Even at 2.3 watts/gallon I would consider using DIY CO₂...

I have two "Satalite" PC and think they make wonderful lights (for the price) as long as heat is not an issue for you...I run mine over an open top tank with no canopy so it is not an issue.

My 55 gallon display tank will have a 2x65W power compact light fixture. The bulbs are the same 6700K/10000K like I got for the 10 gallon, just in the bigger 65W size.

OK the water is still cloudy and there aren't any significant plants in there yet, but here is what the new light strip looks like.

There are 5 rosy red fathead minnows in there if you can find them.

I'll get some better pictures when the water has settled down and there are some more impressive native plant growth in there.

You can also see the fine sifted topsoil substrate that I laid down below the streambed mix that is on the top layer.

Looking good. My last tank was a 55 gallon with 2x 55w PC on it, and it was more or less a success. I think it's a good amount of wattage for a tank without CO2 fertilization.

Nowadays, I run 2x 6700K and 2x 9325K (220w total) on my planted tank. I think the color spectrum of the bulbs is mostly an aesthetic choice, but the 9325K is held in high regard by some folks. I mostly want good color rendition and affordable replacement bulbs. In terms of the latter, I think you'll find the 65w format to be a good choice.