Chit Chat Lurker

[Steve H.]

Hi all!

I have been lurking this section of the forum because I would like to have a planted tank.
I have read many of the threads in the resourse section to try and get my head around how to do this. Its a little more involved than I originally thought, but still set on giving it a go.

My question is about lighting. That's where I should start right?
I am working with a 10gL tank that came as a kit. Everything I have read so far has refers to tube lighting T5 or T8...let's forget for the moment that I have no idea what that means. My tank did not come with that ballast set up. It came with a 15w incandescent bulb with the normal screw in, and when it burned out I replaced it with a 25w "equivalent" soft white spiral floresent. This bulb does not say if it is T5 or 8, but is 2700k.

Can either of these bulbs support live plants?
And if they can I am guessing the 15w would be a low tech set up, and the 25w would require a high tech set up?

Thanks for any and all responses!

 

[OldMan47]

I have had some success growing plants in a 10 gallon using a 13W screw in spiral. It is rated to be equivalent to a 60W incandescent but the real number is somewhat less than you would see from 13W of fluorescent because a spiral has lots or "restrike" due to its shape. Thia puts you into the low light regime. With a 25W equivalent you are at far less than I have seen succeed but it is fine if you just want to light up enough to see your fish. If you want to grow plants go as high as you can fit into your fixture without exceeding its wattage rating. If it is only rated for 15W, that 13W spiral will be about all you can have. That puts you solidly into a low light only regime.
One of the first things you need to do is avoid being misled by the claimed light. You go by the real wattage for a spiral and you can't grow many plants at all under an incandescent without overheating your water. A lot of the energy you put into an incandescent turns straight into heat. That is why the fluorescent lights give so much more efficient lighting. Much of the energy, but not nearly all of it, goes into light instead of heat.

 

[Mcbenthy]

Hi all!

I have been lurking this section of the forum because I would like to have a planted tank.
I have read many of the threads in the resourse section to try and get my head around how to do this. Its a little more involved than I originally thought, but still set on giving it a go.

My question is about lighting. That's where I should start right?
I am working with a 10gL tank that came as a kit. Everything I have read so far has refers to tube lighting T5 or T8...let's forget for the moment that I have no idea what that means. My tank did not come with that ballast set up. It came with a 15w incandescent bulb with the normal screw in, and when it burned out I replaced it with a 25w "equivalent" soft white spiral floresent. This bulb does not say if it is T5 or 8, but is 2700k.

Can either of these bulbs support live plants?
And if they can I am guessing the 15w would be a low tech set up, and the 25w would require a high tech set up?

Thanks for any and all responses!

Okay, quick lesson in lighting terminology

T12, T8 and T5 are all styles of flourescent bulbs with the number relating to the width of the bulb, in general, T12 is very old and obsalet (for aquaria, not shop lighting) and is the lighting that was used when talking about the 'Watts per gallon' rule (hence why that rule is less valid now). T8 is old, but still very popular. T8 is more efficient than the t12 bulbs of old, and you get more PAR (Photosynthetically Active Radiation - 'good' light, but a PITA to measure ) for the same amount of energy per second (or Watts ). T8 often fir T12 fittings, but you will be better with a T8 setting if looking to set one up. Because of T8 being more efficient, the WPG (Watts per gallon) rule starts to lose relevence. T5 is the latest flourescent bulb. More efficient again, you really start to throw the old WPG rule out of the window here! T5 are availiable in a variety of different styles (hence all the letters after like 'T5HO') - these are just bulbs that will take more energy whilst being the same lengths as their 'weaker' T5 siblings.

N.B. all flourescents with the same light temperature rating (Kelvins or 6500K, for example - more on this later) will have the same ratio of wattage to PAR, it's just that you will get more watts of light given out for each watt used as you go from T12 > T8 > T5, so the WPG rule can be adapted by a pure scaling factor (so multiply the wattage of your T5 bulb by ?1.8? - can't remember the number off the top of my head - to get an equiv T12 wattage which you can then apply the WPG rule to )

TL;DR - T12 = bad, T8 = Standard, T5 = better. WPG rule needs updating.

Onto the 'Light Temperature' (But hey, it's light! it's waves in the electromagnetic spectrum, it can have temperature, it's a blasted colour!!), well, actually it's not the temperature of the light, per se. It's the temperature that purfect block box radiator would be to emit that spectrum of light. For example, the sun is 10,000K (the K = degrees Kelvin, which is science for degrees Celcius, but with 0 at 'absolute zero', not where water freezes), and so the spectrum the sun sends out (it's visible light part anyway) is 10,000K. Plants grow best with a spectrum around 6500K - 9000K. marine bulbs like a bluer light which is >10,000K. Lower light temperatures are redder, now if you look at your plants, they are green. This means the light they don't use is green (hence why you can see it, they don't want it, so it is reflected). So your ideal light spectrum is one that has loads of energy on either side of the green bit. Look up a couple of 'black body spectra' and you should get a good idea

TL;DR - 2700K is the colour of light emmited, it is too low. Look for 6500k-9000k (any bulb in that region will suit your needs well)

Overall: The WPG rule is based of flourescents, so ignor the 'equivalent to' wattage. It is a 25W bulb for our purposes. However it is a 25W bulb that wastes a lot of light from lighting up the inside of the coil and the roof and the sides and anywhere that isnt a lovely green plant

Theoretically, it could work with a 25W screw bulb, it's far from ideal due to the coverage you will get (more light in certain parts) and the wastage, but it can work. However that colour rating is too low to do much. Look at replacing it with a nicer colour bulb and low tech plants because you don't have as much light as you would think (if you wanna go by the WPG rule, I would guesstimate at 0.8-1.2 WPG equivalence).

Expect edits if/when I spot silly errors, and I will happily elaborate if you want

Hope that helps

 

[Steve H.]

I have had some success growing plants in a 10 gallon using a 13W screw in spiral. It is rated to be equivalent to a 60W incandescent but the real number is somewhat less than you would see from 13W of fluorescent because a spiral has lots or "restrike" due to its shape. Thia puts you into the low light regime. With a 25W equivalent you are at far less than I have seen succeed but it is fine if you just want to light up enough to see your fish. If you want to grow plants go as high as you can fit into your fixture without exceeding its wattage rating. If it is only rated for 15W, that 13W spiral will be about all you can have. That puts you solidly into a low light only regime.
One of the first things you need to do is avoid being misled by the claimed light. You go by the real wattage for a spiral and you can't grow many plants at all under an incandescent without overheating your water. A lot of the energy you put into an incandescent turns straight into heat. That is why the fluorescent lights give so much more efficient lighting. Much of the energy, but not nearly all of it, goes into light instead of heat.

Thanks! And thanks for the quick reply.

That gives me a starting point. I originally replaced with a 40w equivalent, but it was "day light", and it made the tank look like a hospital waiting room. It was just too white.
That's why I went down to the 25w. They make a "soft white" which has a little more yellow/Orange to it, and I will look for that when I go to pick up a 60w equivalent.
I never noticed the word "equivalent" until getting the details for this post. And, now I see on the package where it shows actual watts. Even the 40w is only 7w actual.

Thanks again!

 

[Steve H.]

So, I could not wait and stopped for a 60w on my way to work. I had 3 choices "soft white"=2700k, bright white=3500k, and daylight=5000k.

Now I know I did not like the look of the 40w day light, but I chose the 60w dsylight because it was the highest.

Good choice, bad choice, or K number does not really matter?

 

[stu40]

Nice post McBenthy.

i don't know if it's right or wrong but it's a good read.It was right with it up till 'T12 is very old and obsalet '

My question would be (and i'm not saying it's wrong), but you say 'plants grow best with a spectrum around 6500K - 9000K'. where did you get that conclusion from?
Everything i've read, on here, and elsewhere, seems to indicate that plants adapt to whatever colour temperature is available.

 

[ian]

Plants will adapt to any Kelvin of light, kelvin is purely for aesthetic purposes.

 

[Steve H.]

Plants will adapt to any Kelvin of light, kelvin is purely for aesthetic purposes.

Sweet....I find the soft white-2700K much more appealing!

 

[Steve H.]

Plants will adapt to any Kelvin of light, kelvin is purely for aesthetic purposes.

Sweet....I find the soft white-2700K much more appealing!

 

[Mcbenthy]

Nice post McBenthy.

i don't know if it's right or wrong but it's a good read.It was right with it up till 'T12 is very old and obsalet '

My question would be (and i'm not saying it's wrong), but you say 'plants grow best with a spectrum around 6500K - 9000K'. where did you get that conclusion from?
Everything i've read, on here, and elsewhere, seems to indicate that plants adapt to whatever colour temperature is available.

Plants will adapt to any Kelvin of light, kelvin is purely for aesthetic purposes.

Plants will utalise any and all radiation that falls into the absorbance spectrum of chlorophyll. That is light of the correct wavelength to start the electron cascade in the Fe-Mg (I seem to remember it being manganese, but it was a couple of years since my last bio-inorganic lectures) cluster. (spectrum here: http/www.cbu.edu/~seisen/ChlorophyllAbsorption.jpg)

em radiation outside of this spectrum cannot be utalised. So, the best kelvin rating to have is a rating that gives as close to that spectrum as possible. If you use a kelvin that is less desirable (such as one with a higher amount of energy distributed in the green end of the spectrum), then you are 'wasting' the light, and will get a lower PAR from the same wattage. As I mentioned before, it is PAR that matters, and not wattage, but wattage is easy to measure, PAR isnt

I can't find any great examples of colour spectrum for 6500K - 9000K, so I'm going to be lazy and suggest you have a look for that yourself (however, there are spectra on the sides of the boxes that you buy the tubes in, if they are Juwel/arcadia etc. Arcadia's website has a couple of spectra that are a bit small, but I will link them here: http/www.arcadia-uk.info/userfiles/LED_models.jpg) and for the 2500K spectrum (http/en.wikipedia.org/wiki/Filepectral_Power_Distributions.png).

Also, apologies for the dodgy spelling etc

I hope this clears it up a bit more, again, I'm happy to elaborate on further points if you wish

 

[SaTiVa1984]

em radiation outside of this spectrum cannot be utalised. So, the best kelvin rating to have is a rating that gives as close to that spectrum as possible. If you use a kelvin that is less desirable (such as one with a higher amount of energy distributed in the green end of the spectrum), then you are 'wasting' the light, and will get a lower PAR from the same wattage. As I mentioned before, it is PAR that matters, and not wattage, but wattage is easy to measure, PAR isnt

So is my new bulb i just bought pants?

Arcadia Freshwater Lamp 38W 42" 1047mm.

The Freshwater Lamp has been specifically formulated to provide a uniquely created colour temperature, peaking in the green part of the spectrum. It also provides superb colour rendition, enhancing all the natural colours to be found within typical freshwater aquaria.


* Shows the rich greens of plants.

* Encourages plant growth.

* Brightens the natural colours of fish.

Sorry for thread hijack

 

[Mcbenthy]

em radiation outside of this spectrum cannot be utalised. So, the best kelvin rating to have is a rating that gives as close to that spectrum as possible. If you use a kelvin that is less desirable (such as one with a higher amount of energy distributed in the green end of the spectrum), then you are 'wasting' the light, and will get a lower PAR from the same wattage. As I mentioned before, it is PAR that matters, and not wattage, but wattage is easy to measure, PAR isnt

So is my new bulb i just bought pants?

Arcadia Freshwater Lamp 38W 42" 1047mm.

The Freshwater Lamp has been specifically formulated to provide a uniquely created colour temperature, peaking in the green part of the spectrum. It also provides superb colour rendition, enhancing all the natural colours to be found within typical freshwater aquaria.


* Shows the rich greens of plants.

* Encourages plant growth.

* Brightens the natural colours of fish.

Sorry for thread hijack

To me it sounds like a 6500K bulb (please can you check for me?), in which case there will be noticable peaks in 3 regions, the green being one of them. The plants will use the blues and reds to photosynthesise and the green will make the plant colours 'pop'.

As said before, a plant will use any light it can, you would have to use a purely green light (or low IR/high UV if you wanted to not be able to see...) for the plants to not be able to use the light.

My big bug-bear about aquatic lighting is that people get taken for fools when buying by companies such as Arcadia and Juwel with very highly priced bulbs being sold as superior, when infact they are just a suitable temperature, and you could go to B&Q for an equivalent Philips buld, armed with the correct information.

Regardless, your bulb will be fine so long as it isn't a filtered light source (it isn't, don't worry ), but check the information on the packaging/bulb and you will have a better idea (as well as the info to replace it cheaper! )

 

[Steve H.]

Nice post McBenthy.

i don't know if it's right or wrong but it's a good read.It was right with it up till 'T12 is very old and obsalet '

My question would be (and i'm not saying it's wrong), but you say 'plants grow best with a spectrum around 6500K - 9000K'. where did you get that conclusion from?
Everything i've read, on here, and elsewhere, seems to indicate that plants adapt to whatever colour temperature is available.

Very interesting. I finally see what you're saying.
I can speak intelligently when I want and need too. Especially when I know the subject matter, but sometimes I just need someone to "dumb it down" for me so I don't have to read it 10 times.
Remember I am in my infant stages of this hobby. Catch me in a month or two after all this research and discussion. I should be up to speed by then.

So, as many things in life, I am limited in so far as what is available out there with my particular set up. The maximum K rating I could find easily is 5000.

Plants will adapt to any Kelvin of light, kelvin is purely for aesthetic purposes.

Plants will utalise any and all radiation that falls into the absorbance spectrum of chlorophyll. That is light of the correct wavelength to start the electron cascade in the Fe-Mg (I seem to remember it being manganese, but it was a couple of years since my last bio-inorganic lectures) cluster. (spectrum here: http/www.cbu.edu/~seisen/ChlorophyllAbsorption.jpg)

em radiation outside of this spectrum cannot be utalised. So, the best kelvin rating to have is a rating that gives as close to that spectrum as possible. If you use a kelvin that is less desirable (such as one with a higher amount of energy distributed in the green end of the spectrum), then you are 'wasting' the light, and will get a lower PAR from the same wattage. As I mentioned before, it is PAR that matters, and not wattage, but wattage is easy to measure, PAR isnt

I can't find any great examples of colour spectrum for 6500K - 9000K, so I'm going to be lazy and suggest you have a look for that yourself (however, there are spectra on the sides of the boxes that you buy the tubes in, if they are Juwel/arcadia etc. Arcadia's website has a couple of spectra that are a bit small, but I will link them here: http/www.arcadia-uk.info/userfiles/LED_models.jpg) and for the 2500K spectrum (http/en.wikipedia.org/wiki/Filepectral_Power_Distributions.png).

Also, apologies for the dodgy spelling etc

I hope this clears it up a bit more, again, I'm happy to elaborate on further points if you wish

 

[SaTiVa1984]

To me it sounds like a 6500K bulb (please can you check for me?), in which case there will be noticable peaks in 3 regions, the green being one of them. The plants will use the blues and reds to photosynthesise and the green will make the plant colours 'pop'.

As said before, a plant will use any light it can, you would have to use a purely green light (or low IR/high UV if you wanted to not be able to see...) for the plants to not be able to use the light.

My big bug-bear about aquatic lighting is that people get taken for fools when buying by companies such as Arcadia and Juwel with very highly priced bulbs being sold as superior, when infact they are just a suitable temperature, and you could go to B&Q for an equivalent Philips buld, armed with the correct information.

Regardless, your bulb will be fine so long as it isn't a filtered light source (it isn't, don't worry ), but check the information on the packaging/bulb and you will have a better idea (as well as the info to replace it cheaper! )

The only info i see on the box is: 7,500k CRI Class 1, the graph has 3 peaks in it, 1 in the green, 1 very close to the dark blue, and 1 in the orange close to the red.

 

[ian]

your new bulb isn't pants...it will grow plants end of. The above is mainly written by marketing companies regarding selling 'planted' lights tubes. As we know you can buy tubes from lamp specs for a fraction of the price of that of a hagen plant tube.

I'll have a look for the stuff on the Barr report regarding Kelvin ratings. The Barr report is a place where all the boffs hang out. It was decided that although there must be a specific optimum growing range, it isn't as in between as the jpg above, which incidentally was produced by a plant tube company.

I shall find the stuff when i get home from work.

I will just add for anecdotal evidence that i have grown plants under a house CFL, with a K of 2800.

please don't get caught up in the K ratings, light will grow plants, not K ratings. As above, it's the PAR that matters.