new light fixture!!

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Aquarium Advice FINatic
Nov 2, 2005
chicago ridge, illinois
so at the hardware store today i seen a 24 inch dual fluorescent fixture with a lighting covering already on it for 15 dollars! so i bought it and it takes either 2 17 watt t8 or 2 20 watt t12 but doesnt a t8 only have 20 watts at 24 inches but will it matter i was going to get 2 t12s anyway and with the 40 watts on my 20 gallon tank will it be so much that i need co2?
It probably doesn't have a reflector, so I bet you would be ok without Co2. You might want to look into Flourish Excel if you have some algae problems, but I don't think it would be worth setting up a DIY Co2 system.
no it doesnt have any metal around it which would be a reflector so ya ill try to do flourish excel with the 40 watts and if i see algae ill just take 1 out and run with 20 and they see if i want to do co2

at the lfs around here i dont remember them having flourish exel but i think they had flouris iron and just flourish, which one of those would work?
Put 17w T8's in it, they are brighter for the power consumed. (T8 = 141% of T12 light per watt) so 17w T8 = 24W T12 :)

Also, next time you are at home depot you can pick up some aluminum tape, put this on the fixture and it should help increase the light.
hmm thats interesting i thought t12s would be better bc they are thicker hmm thanks for saying this now when i go, ill buy two t8s at 24 inch with 17 watts thanks! but when i was there last if i remember correctly the t8s where 24 inch 20 watts will it still be better than a t12? also if i have an option of t5 t8 or t12 all same watts same lenght wat should i get?
T8's are 17w
T10's are 20W
T12's are 20W

T10's are exclusive to Hagen and come in the "glo" series, with Sunglo being the best for plants, seconded by Powerglo and Aquaglo. I won't recommend the floraglo since it's so dull.

Try going back to the Local hardware store and getting T8 24" Philips daylight deluxe or natural sunshine. both are excellent plant bulbs. (and cost about 2$ each)

I wish we still had the kudos system, so I could toss a few your way for your work on this thread.

Nice job! :)
No, they require an electronic ballast or a rapid start ballast rated for T8's. T8 bulbs operate typically on a higher frequency which get's rid of the hum associated with fluorescent lights.

That being said, I currently have a T8 and a T12 on a single T12 fixture and it works but the T8 takes a bit longer to fire and may not be consistant. I have 5 bulbs over my tank so one taking an extra 30 secs to fire or up to an hour doesn't make a huge difference to me.

Malkore: I spend far too much time reading. :) We all share what we know, and learn from eachother :)
ya before i came to this site i didnt know anything really and now i feel very educated all becasue of you guys and your helpful ness and to think one lfs around here wanted to give me 2 chiclids for a 5 gal tank!!!

when i went to home depot the lights they had where the daylight and natural sunshine but they only sold them in 2 packs of 48 inches so ther only t8 24 inch was soft white which arent really white at all and are more of a yellow so i think ima look around at some more home depots and see what they have any other suggestions maybe internet sales?
Sorry, I just checked and philips only makes soft white for 24" T8..

Find a store that sells GE Ecolux light bulbs. you are looking for
Product Code	Description	     Watts	In.	CRI	Color Temp	Initial	Mean	Life 3 hrs./Start	Case Qty.

10415	      F17T8/XL/SPX50/ECO	17	  24	  85	5000K	      1300	  1235	24,000	             24

They are General Electric Ecolux T8 bulbs 24" with a colour temperature of 5000K (this will be on the package or on the tube) write down the part number (description) and you will hopefully find one that is the same.
Most fluorescents will grow plants, It's just the look to you and certain temperatures (kelvin) of the bulbs have a tendancy to balance the spectrum. so the closer you are to 5000Kelvin the better, typically the higher you go (towards 10,000Kelvin) the more blue there is in the bulb and the better the fish look. Blue is also more able to penetrate water, mainly due to it's wavelength being shorter. With no reds however you will find that your plants will wither. so it's all about keeping a decent balance.

Cool white (soft white isn't listed as 24" T8) is 4100K making it more towards the red The actual look in water will be yellow. the CRI of 70 also indicates the fish will not look that vibrant.

If you are looking online the best price for a bulb that will work 2 x Sunglo bulbs for 15$ ( ) they automatically combine shipping.

Ebay is a good source for a lot of things. but I would call a couple larger stores (Try walmart, they're everywhere) and ask if they carry GE bulbs.

*I am not affiliated with the above store, I found them in google.
so the plants will still grow with the kelvin now but its just a look of the light?
the thing i liked about my old flora glo was the plants were so vibrant and now i see a lot more of browns in my tank whichj is becuase like you said the soft light is 4100 k so i dont know and is the glo series t10 or t8?
im usually my own worst critic and i have to get used to things so more i look at it, itll grow on me more so i think ill just keep it at this wattage and its good atleast that i got 19 more watts so i think my plants will be happy even if im not with the look
Plants will grow anywhere there is photosynthetic radiation (mainly blues and reds) So balancing these 2 will optomize the ability for the light to be consumed by the plant. Plants may grow with strong blues, but with little to no reds this becomes a limiting factor. so if you look at the spectral output of the sun you will see the relative levels of output by the sun, the closer you can get the reds and blues to that output, the better your plants will grow.

5000K - 6500K tends to have this balance in correct proportion making the brightness of the lamp in both spectrums good. Think of it as engine power and brakes. you need them both to be as good as possible or one is not as useful. (huge power, no brakes makes for a good headline on the 6:00 news, no power and huge brakes makes for a very slow ride).
so the one i have now which is 4100k is not actually too bad because its close to mid range but probably just has more reds than blues correct? so that way ill probably just keep this bulb and if i do come across the ge one with more mid range later ill pick it up

thanks for putting up with my noobness, but atleast im learning stuff whihc =doesnt happen at the lfs, last time i asked them about lights they didnt know anything
If you have 2 bulbs, you could split them up, 1 bulb in the lower range, like the 4100k, and the other in the upper range, like 10000-12000k. I use both 6400k and 12000k in mine. The lower is more yellow, which had more reds, and the 12000k for white and blue. I also use actinics. The fish do look awsome. :)
I was teaching the guy at the LFS about lighting.. and he does know a lot.. we sorta feed off eachother which is mutually beneficial, I'll also help customers out when they are busy and the customer is asking a lot of questions.. Occasionally I learn stuff from people there aswell, I was talking to a guy there that reminded me that everything reflects back the colours they don't absorb. I had forgotten about that from highschool. So those red plants, they use red/blue(Chlorophyll) and contain another pigment that will absorb large quantities of green(Carotenoids are yellow/orange or red plants, Phycocyanins are blue/purple plants) which would lead me to believe to get things to look more red you would need to overload the red spectrum, but that would also make it look falsely red, so the mystery on that one is still not closed.. (but starving the clorophyll by nutrients will bring out the colours by dominance of pigmants but plant growth may suffer)

Yes, the 4100k will do fine for quite a while, just keep an eye out for algae which has always attacked my tank when I used strong red bulbs (2500k) but I don't forsee you having a problem.

Sorry for the speech there, just figure the more someone understands about what the plants are looking for, the more then understand about what is needed for growth.

actinic is borderline violet light (very rich blue). I'm still chewing over whether they have an effect on plant growth and what degree, their output is within the photosynthetic curve.
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