wee quickie....may be a stupid q, but do they?
i get the idea of 'its cooler so can be closer to plants ,therefore better' but does the glass reduce lumens or whatever getting through?

Yes - they do, and the reflector in them is as well. You can improve matters by taking out the reflector that comes with it inside the tube, and then mounting the tube in a Dutch Barn reflector or whatever.

how much of a detrimental effect do you see?
are they worth the doe?
was thinkin of pickin one up this week but will be cash from an expensive grow shop (bastards)

You can buy from Greens with cash

Glass, afaik, will block UV as well, something that helps improve taste and potency. However this is a somewhat small-ish reduction in quality.

order, then send money/postal order in post????

??

Here you go man

Greens get my vote... very good company, I use them whenever I can

awsum eri ta..
everything your tin hat wearing stoner wants

they also have a coolreflector in flatpack form, looks like it has a decent sized and shaped reflctor too.

Check out Felix's posts on UV. Or ask Scraglor.

I never use my cooltubes they're shit, get a parbolic and better extraction you'll never look back and heat pproblems will be long gone.

i'll check that out

It depends on what you are dealing with space wise, I couldn't grow without them, but I have a long narrow room with 2 x 600's so the light doesn't spread far and I can get the bulbs closer or the plants bigger depending on how you look at it, as the fan draws out the heat... Does the light reduction from the glass outway the reduction in light spread? Not sure... If I shine a torch on a wall I see a circle... if i step forward a foot and slide a sheet of glass in front of the torch is it a brighter or darker circle I see? if you know how thick the glass is this is just a maths question that can answered exactly... I don't care tbh though they work for me

And in the end that is what it is all about and why we share our stories.

Most choices in life, as in growing, allow you some pluses as well as minuses. It's up to each grower to asses their own grow spot and what it needs. And what any particular tool and/or solution offers to address those needs.

Cool Tubes are very useful in certain situations.

I was thinking about getting myself one of these

http://www.greenshorticulture.co.uk/Grow-L...-150mm-1331.asp

I grow in a 1.8m tent so height and heat can be an issue.

Any thoughts much appreciated.

heat wise 1x600 is my max in the winter, i will replace it with a 400 next summer, if that dont do the job i will have use an alternative, i'll keep reading the posts about the topic.

I would agree with that as well, I've grown plants out to maturity in a 4x2x4 box with a 600w using my cooltube but if you've got the height, width and depth scrap 'em.