# Light sitting on glass lid?



## Zer0 (Mar 25, 2012)

I have a 50w agro-light from home depot to grow plants, and a glass lid. I was just wondering if the glass will heat up and melt stuff or something along those lines?

And whole were on the light subject, is a 50w plant grow out bulb good enough for my 18" tall tank? Should I have gotten something like a 75w bulb? or 120w?


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## goof901 (Jan 9, 2012)

50 w fluorescent right?


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## Zer0 (Mar 25, 2012)

goof901 said:


> 50 w fluorescent right?


Maybe? Not sure if it's flourescent or.. a regular bulb? lol.


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## Zer0 (Mar 25, 2012)

Zer0 said:


> Maybe? Not sure if it's flourescent or.. a regular bulb? lol.


Philips Agro-Lite 50-Watt R20 Indoor Plant Flood Light Bulb* 415315 - Lighting - DealTime

Dis bulb^


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## goof901 (Jan 9, 2012)

is it spiral or just a circular-ish shape?


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## Zer0 (Mar 25, 2012)

goof901 said:


> is it spiral or just a circular-ish shape?


Check my previous reply


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## goof901 (Jan 9, 2012)

does it put out a lot of heat? looks like an incandescent bulb to me, but just wanna make sure


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## Zer0 (Mar 25, 2012)

goof901 said:


> does it put out a lot of heat? looks like an incandescent bulb to me, but just wanna make sure


mmm.. to be honest, I've had the bulb running for the past two hours and my glass lid is still cool to the touch, not even warm. However, when I stick my hand inside the cage, I can feel the heat radiating from it about... 15" down. Can't feel the heat with my hand near the bottom of the cage.

However, it's extremely hot when I touch the part of the glass that is directly under the bulb. The bulb is in one of those standard metal fixtures you see all over home depot.. will that be a problem? Should I find a way to raise the fixture up off the glass?


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## goof901 (Jan 9, 2012)

you wanna get rid of that thing asap and get a cfl (compact fluorescent light) with a color of 6500k. those are best for plant growth. this is that will happen if u use that bulb that u have much longer. 
http://www.dendroboard.com/forum/parts-construction/80944-cracked-viv-class-help.html
here are some links to 6500k cfl bulbs
2nd one from the bottom
New England Herpetoculture LLC - Bulbs

6500K Spiral Compact Fluorescents - 6500K Spiral Compact Fluorescents | Josh's Frogs

Google

as long as your light fixture doesn't have a dimmer, than you can just screw these cfl's into the light fixture you currently have. once you switch over, then there shouldn't be any issues with putting the light right on the glass as these bulbs don't give out a lot of heat.
if you had frogs in there, they will get cooked by this bulb


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## Zer0 (Mar 25, 2012)

goof901 said:


> you wanna get rid of that thing asap and get a cfl (compact fluorescent light) with a color of 6500k. those are best for plant growth. this is that will happen if u use that bulb that u have much longer.
> http://www.dendroboard.com/forum/parts-construction/80944-cracked-viv-class-help.html
> here are some links to 6500k cfl bulbs
> 2nd one from the bottom
> ...


Damn dude, thanks for letting me know about that light. I mean.. the glass lid I have is just some $2 piece of glass I cut out and could replace in a heartbeat, but I would never want to have to deal with cracked glass or whatever. 

When you said my frogs would get cooked, you meant with that CF bulb you linked me to in Josh's site? Or the incandescent bulb? I don't and won't be keeping frogs.. just plants and maybe a vampire crab.. do you think that bulb will be fine for my plants?

Also, what wattage do you recommend over my 18" tall tank? It's 12x12x18


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## goof901 (Jan 9, 2012)

the incandesent will cook your frogs. 6500k is ideal for plants, that's what i (and everybody else) use. about 23 watts is perfect for your vivarium.


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## killerecho (Jul 27, 2011)

The same thing (glass top cracking) happened to me with a 40W night heat bulb. The glass will crack because of thermal stress. Basically, the area heated by the bulb will try to expand rapidly while the part at room temperature holds the same shape. That expansion has a stretching effect, and since glass is a brittle material, it will fracture. 

These incandescent bulbs burn extremely hot and really are meant to be used on a metal screen top. If you have to use the bulb, find a way to lift or prop up the fixture so that there's some distance between the bulb and the glass.


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## Zer0 (Mar 25, 2012)

What would you guys say to these bulbs here? Amazon.com: EarthTronics CF23DL4BT2 23-Watt 6500K Micro Spiral Compact Florescent Light Bulb, Day Light, 4-Pack: Home Improvement


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## yours (Nov 11, 2007)

I would definitely scrap an incandescent bulb, and I would pass on a compact fluorescent bulb as well. The true golden nugget is the LED bulb to be honest! Way more heat efficient, electricity efficient, and superior quality light! Hit up Todd from ligjtyourreptiles.com, if you have an exo hood, you can shoot for one of the LED 9 or 11 watt bulbs and they'll screw right in! 

You will NOT be disappointed!


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## yours (Nov 11, 2007)

Also, with the LED lights, you do not have to elevate them off of the top surface of your glass tank. They can rest directly ontop because they do not get hot.


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## killerecho (Jul 27, 2011)

What are you keeping in the tank? What kind of plants, and animals, if any?


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## mordoria (Jan 28, 2011)

Zer0 said:


> What would you guys say to these bulbs here? Amazon.com: EarthTronics CF23DL4BT2 23-Watt 6500K Micro Spiral Compact Florescent Light Bulb, Day Light, 4-Pack: Home Improvement


Yea, those bulbs are good. Stick to the spiral type fluorescent. A single 23w-26w should be ok for now. Dont put the lighht directly on the glass. Try and raise it up a few inches.

"Yours" is right. LED are the best light/heat ratio but they are 25$ each. Try the Spirals and see how you like the heat and growth. Remember no higher then 80 degrees


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## jacobi (Dec 15, 2010)

Zer0 said:


> Maybe? Not sure if it's flourescent or.. a regular bulb? lol.


Backtracking a little bit from the good advice given already, before anything else, do you know what the difference between a fluorescent and incandescent? I'll assume not, based on the post I quoted. 

An incandescent bulb is what, i think, you are calling a 'regular' bulb. There are various types, but basically they work by passing electricity through a piece of metal. This heats the piece of metal up, producing a lot of heat, and some usable visible light. That's why they are considered energy inefficient, since they use a lot of electricity, and waste a lot of it as heat. For our purposes they are no good, since the heat can be harmful to the tank and its inhabitants, and it isn't the right kind of light for the plants. (I'm not going into UV here!)

A CFL bulb is a Compact Fluorescent Light. Basically they are the long (2-4 feet) light bulbs you see in ceilings, but in a spiral shape which uses less space (not discussing ballasts here!) and can be used in a regular light socket. They use less electricity and put out less heat, making them more suitable for our tanks. The ones suggested by the posters above are the ones with both visible light, and light that can be used by the plants for photosynthesis.

LED's take it a step further, and use very little electricity compared to incandescents and CFLs and produce much less heat than either. LEDs can be manufactured to produce light in specific spectrum ranges, making them great for our purposes (visibility and photosynthesis).
Hope that was useful. 


Jake


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## Roadkillstewie (Feb 15, 2012)

> A CFL bulb is a Compact Fluorescent Light. Basically they are the long (2-4 feet) light bulbs you see in ceilings, but in a spiral shape which uses less space (not discussing ballasts here!) and can be used in a regular light socket. They use less electricity and put out less heat, making them more suitable for our tanks. The ones suggested by the posters above are the ones with both visible light, and light that can be used by the plants for photosynthesis.


 A point of accuracy, CFL's lamps (more accurately, power compact floursecent lamp) are also http://upload.ecvv.com/upload/Product/200801/200752411111377633_Power_Compact_Fluorescent_Bulb.jpg


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## jacobi (Dec 15, 2010)

Roadkillstewie said:


> A point of accuracy, CFL's lamps (more accurately, power compact floursecent lamp) are also


Point of accuracy? C. F. L. = Compact Fluorescent Light. It would be a misnomer to say "compact fluorescent light lamp". There are many more shapes than the spiral ones I referred to. The helical integrated ballast compact fluorescent lights (aka spiral) are the most common.

Jake


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## Zer0 (Mar 25, 2012)

Well, regardless, I got the right bulbs that were suggested to me and I got 4 of them for $12 so I think I'm set. Also, to combat the effect of heat on the glass, I cut out 2 pieces of glass and siliconed them lengthwise on the glass lid and I just prop the light on that. There actually isn't any heat issues at all, and my tank stays cool as well. 

Problem solved.


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