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View Full Version : Best Galss for Spash Guard?


vishboy
06/06/2006, 04:22 PM
I was wondering what the best glass for 250w MH splash gurad was. Tempered or not tempered?

Thanks,
Vishboy

shoddyk
06/06/2006, 04:46 PM
tempered glass

vishboy
06/06/2006, 05:11 PM
Okay, sounds good. Should I get regular, starfire, or low-e (might nt exist, but I thought I heard it mentioned somewhere)?

vishboy
06/07/2006, 12:47 PM
Ok, Low E does exist.

nemo g
06/07/2006, 01:27 PM
low-e does the best job of reflecting uv but at a serious cost. at least 20% of heat will also be reflected back into the fixture. this will obviously have an impact on bulb life as well as anything else (t5, ballasts) that are housed in the fixture.

do some research, uv is not a serious consideration when it comes to artificial lighting. in the zooligical world, lamps are specifically designed for uv output, and even then the distance transmitted is minor; less than 12" for most flourescnet bulbs and 3-6 feet depending on the power of the newer mercury vapor type bulbs. this is all without any type of shielding because any type of glass will relfect uv to a crtain degree.

which goes to the actual purpose of low-e glass. the purpose of using this glass isnt uv, its the fact that it relfects solar heat. thus, any architecture with lots of windows would be at risk of bcoming a green house and the sums to cool such designed buildings or rooms would become astronomical. with the 20% of heat reflected, cooling costs are much lower.

try some reading on chameleon care, these little guys need major uv for bone health. and youll see that any glass shield kills any usefull uv. this is why youll never see anytupe of glass between a uv needing reptile and its light source. and why youll never see one siting by a window, as it will recieve no uv there as well.

try and findout how much uv starfire kills. id rather go that route in order to get every watt of light i payed for into the tank.

let me know what you find

LBCBJ
06/07/2006, 01:44 PM
I'm using low-e, you just have to have to get some small fans to keep it cool. There are different types of low-e glass, mainly based upon thickness. Some types block more UV than others (up to 70%), which is why many homeowners use it to prevent the fading of furniture exposed to light. Regular glass doesn't do much, whether its tempered or not, neither does acrylic.

vishboy
06/07/2006, 02:02 PM
I don't need uv filtering glass (SE fixture), I just need something to block any water I may accidentaly splash onto the bulb. If I have to use fans for low-e, it will be off my list. I just want glass to protect the bulb.

Mike.B
06/07/2006, 03:16 PM
<a href=showthread.php?s=&postid=7516415#post7516415 target=_blank>Originally posted</a> by vishboy
I don't need uv filtering glass (SE fixture), I just need something to block any water I may accidentaly splash onto the bulb. If I have to use fans for low-e, it will be off my list. I just want glass to protect the bulb.

same

LBCBJ
06/07/2006, 03:30 PM
Ok, if you're using a SE bulb then I wouldn't even use glass. I would use just plexi-glass or acrylic.

ulua56
06/07/2006, 03:35 PM
I use 5/16 tempered glass under my 400 watters, $20 for a 12x12 at my local glass store, be careful, you can take a hammer to it and it would'nt break, but when cleaning it in the sink don't hit the tip or side hard. It will shatter faster than my ex's fake diamond. :lolspin:

ulua56
06/07/2006, 03:39 PM
never, flash point is 800 degrees for acrylic glass only. I have SE.

nemo g
06/07/2006, 04:29 PM
if you get glass, get it tempered.

it is stronger, and if it does break, itll shatter into bits rather than large shards than are far more dangerous to you, coral, and fish.

also compare the benefits of glass and plastic.

the glass will hold its clarity longer due to the fact that the it holds up better to cleaning (reason why some avoid acrylic tanks).

i have a 2 month old satellite fixture that is already showing wear after only a few cleanings. probably due o the salt spray being abrasive and plastic softer than glass.

some high quality acrylic will be clearer, but not after it gets wear on it.

LBCBJ
06/07/2006, 05:42 PM
You dont have to worry about plexi-glass or acrylic shattering though.

Monkey_Bone
06/07/2006, 08:15 PM
Acrylic does filter out UV. So does Polycarbonite. ( any thickness. Its a natural side effect of the molecular structure of acrylic and polycarbonite, but over time it will tend to yellow or white out.)

PLane glass un-tempered ( depending on the type of glass IE starfire, reg glass, optical glass, that green tinted stuff....)
Filters out up to 30% of UV.
I recently purchased a 60"x11.5" piece of 3/16" Low-E, tempered glass and it was only $80 bucks.
To me thats a sound investment.
The knowledge the halide wont break it from theheat, and the Low-E will reflect the UV is a huge load off!
It wont take much of a fan to solve the heat problems either.
If your hood will accept it just put a computer fan or two on it.
a couple 86cfm computer fans set up as a pusher and a puller would keep it plenty cool. Its already sealed ( some what) so the fans would essentialy make a wind tunnel and constantly push out the hot air.
The Low-E will still hold a certain amount of heath though.
( so I am told I havent gotten my glass yet it will be in next week. paid for it in advance)
Just mount the fixture a couple inches higher if you can.
I have mine hanging and on two small pulleys with a SS ring in the pull down/up cable every 3 inches for a 1 foot series and then again at the 2 foot level for maintenance.
Works great so far.


BUT as I just re-read and saw you state you dont need UV filtering! DOUGH!!!!
I would just buy a pane of tempered glass.
G-luck!

vishboy
06/07/2006, 08:26 PM
So, even though the regular glass has a green tint to it, it won't change my color values? I will get tempered glass, but I need to know what kind will give me the least color alteration.

vishboy
06/08/2006, 10:23 AM
And I wont be using acrylic. It would probably melt, or warp, or do something wierd.

vishboy
06/10/2006, 04:49 PM
So will the color be altered?

nemo g
06/10/2006, 05:12 PM
can you tell the color tint through your tank glass??

no, right? i cant. when have you ever heard someone complain abou the color of their halides because of the green glass of their tanks? only the new tech series tanks from oceanic have starfire on the from and sides, unless you order a custom tank from somewhere.

dont worry about it, if you are, get starfire or something of the like. and if it makes you feel better, just find out what the uv tranmission of starfire is compared to standard glass is.

good luck

vishboy
06/10/2006, 06:32 PM
Sorry, reread your post. But just to confirm that the right point is going through:

The slight green tint of regular glass wont affect the color of the light going into my tank?

LBCBJ
06/10/2006, 06:46 PM
Got my low-e today, within 15 seconds it cracked. You have to get tempered.

vishboy
06/10/2006, 06:55 PM
Ok.