# t5 or t8



## phaz3boy (Feb 28, 2012)

I was just wondering which one is better for darts and plant growth. I always get confused on these two.


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## goof901 (Jan 9, 2012)

t5 ho, 6500k is the best.


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## jeeperrs (Jan 14, 2010)

T5 is just a smaller bulb by diameter. I have a 90 gallon and run 4 T5s, lately I have been only running two. I haven't noticed any problems with my plants (actually, I think they like having only two on). The light is primarily for the plants and not the frogs


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## mcaiger53 (Jan 3, 2011)

t5ho's will put out much more light than a t8, especially when used with a good reflector, but more heat as well. You would need half as many t5's compared to t8's
Mike


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## jeeperrs (Jan 14, 2010)

I feel the need to add a little more information. The bulbs you question require you to get more detail for a more accurate response. Most of the plants you will be growing do not require "intensity" of light as they grow in a rainforest under a canopy. T5s are really big in the salt water world because the corals require a light that can penetrate to the bottom of an aquarium where most people put their corals. Water is very difficult for light to pass through making T5s the best choice. Here are a few questions to ask.

1) How long do you want your lights to be on? If you want to have them on for 10 or 11 hours a day I am pretty sure a T8 can suffice.

2) Are you getting a High Output T8? If so, you will have a bulb that has twice the life of the T5. So, you may pay slightly more for the wattage but you replace T8s less often than T5s.

3) What brand of bulb are you buying? Both T5 and T8 have crappy bulbs out there and you will want to get a quality brand. The brand of bulb can have more impact than reflectors. If you have a crap bulb the reflector is bouncing crap light because T8 and T5 is only the diameter and nothing more.

4) Do you already have heat issues? If so, you will want a fan for the T5s (totally ruining the savings in watts for the T5s). 

So, what does this all mean? Well, it means whatever you want. Don't buy the cheapest bulbs out there and you will be fine with either option. If you get a good deal on a High Output T8 then get that if it makes you happy. However, don't think you NEED a T5 because "I" have a T5. I just got a good deal on it and I came from a Coral Reef background where T5s were king. We just don't have any water to fight through in the frog world and now I have learned T8s are just as good, especially if you get a High Output T8 (P.S. I know people growing coral under High Output T8s and coral is more difficult than any plant I have seen).

The final most important thing is what color spectrum are you going to use? Make sure to get something around 6500k. You can get blends of other colors around 3000k which is more red. I use a mix of 6500k and 3000k. I like it and it works for me but you could probably be just fine without the blend.


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## J Teezy (Jan 25, 2012)

as stated it really comes down to the bulbs you get. You can use CFL's that have 6500k color temp. There's even LED bulbs that have 6500k ratings as well. I think the size of your tank would also determine what's best as well. There's all kinds of things with lights. How's your temps? is added temp from lights going to be bad for you, some light fixtures / bulbs are going to produce more heat than others.

Me personnally i'd only use T5 or T anything for like a rack of tanks or a tank that was longer that 2ft, otherwise for single tank less than 2ft i'd probably go with CFL's or LED fixtures with 6500k ratings.


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## ilovejaden (Jan 6, 2011)

neither. Go with LED.


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## Edhurl (Nov 8, 2011)

Hope you dont mind a small hijack, maybe this could help you too. I was thinking of a double fixture with these over 4 ten verts, what you guys thunk?


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## Pumilo (Sep 4, 2010)

That will make a nice, usable, economical fixture Ed.


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## jeeperrs (Jan 14, 2010)

Ed,

I have seen people use similar lights in Saltwater tanks (small ones) and they did fine. Again, it is about what you want to grow. Basic vegetation does great with 6500k but flowering plants tend to need 3000k. So, I would say you should be fine if you are going to grow plants that need moderate light and not bloom. If you feel that you are not getting the results you need you can always make the fixture a shop light or put it in your bathroom  

One disclaimer, you may want to reconsider changing the bulbs to a true grow bulb. Commercial bulbs often create a Kelvin color by the color of the glass. This is very different from the light spectrum it is truly putting out. High end bulbs use to elements like Sodium or even Mercury in Metal Halide lights (that is what gives metal halide that "sparkle" in water aquariums). The materials in the gas tube is what makes high end bulbs worth the money and in turn effect the peaks of the color spectrum for low K bulbs and high K bulbs. Those peaks are what makes flowers bloom and vegetation grow.


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## jeeperrs (Jan 14, 2010)

This is an old post I made a couple years ago. 

I would like to clarify this statement. The Kelvin rating is related to the color of the light. Remember, when you use a prism to break the light you will see colors from red to blue. The higher the Kelvin rating the more blue the light. They get the idea of "temperature" for color based off of the colors heat makes. Think of it this way, "colder" fire is more yellow/red but "hotter" fire (as in a blow torch) is blue. So, the temp is really focused on the color of light.

Now, the reason 10,000K and up work for marine tanks is because water is very hard for some colors of light to pass through. Since it is hard for the reds/yellows to make it through water, you see the blues. The deeper the ocean floor, the bluer it appears. Through evolution corals (actually an algae that lives in the corals) have a need for a specific temp of light (10,000-20,000K). 

Plants on the other hand respond to different color temps. Even though the forest floor has more "shade" the temp of the light is still the same, except it is indirect light. The standard 6500K is good for plants because it has a range of colors plants need. There is some debate over what temps are best for plants. Some articles state that the 3000K lamps are best for plants, as the chlorophyll has a better reaction to those temps. This reaction supposedly will allow the plant to bloom and not stretch for the lighting. The down side is that the 3000k temp has a red hue. Beware, cheap bulbs tend to use coloring in the glass to make it appear a certain K, but the light (energy being emitted) is not really that rating. If you take a poor quality 3000k and put it next to a high quality 3000k, you might think the high quality bulb was 5500K. Look for quality light bulbs for premium plant results. The safe number for plants seems to be 3000-6700K. If you doubt this, go to your local hydroponics store and ask what they use and why they use it. I hope this helps you understand light better


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## Edhurl (Nov 8, 2011)

Edhurl said:


> Hope you dont mind a small hijack, maybe this could help you too. I was thinking of a double fixture with these over 4 ten verts, what you guys thunk?


you thunk I.could get away with one bulb?


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## IHeartFrogs (May 8, 2012)

just go with t5's


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