Why doesn't anyone use T8?

Can anyone explain to me why nobody uses T8s?

Seems most people are using CFL or VHO T5s.

Was just doing some math and thinking about the shape of the lights.

32 watt 6500k on 1000bulbs.com puts out 2100 lumens.
This = 65.625 lumens/watt

GE 32 watt 6500k 48" T8 from your local hardware store puts out 2750 lumens.
This = 84.375 lumens/watt

Seems like there would be less wasted light from a T8 vs CFL because with a CFL the inner side of the CFL coil is just shining on itself. Also a T8 has more surface area to dissipate heat and spread light evenly.

Any thoughts?

I still use T-8's for clones and vegging, I have not sprung for the T-5's yet.

I love my T8's! With 6500K bulbs they work great for seedlings.

Ok so there are people that use T8! Huzzah! I was starting to think I was crazy.

So why don't they come up much during fluoro discussions on here? It's always CFL/VHOT5 vs HID.

Good question. I think most people using Florescent lighting for grows are trying to use them for veg & flower. That is why they are pushing CFLs, HO T-5 and LEDs. I have been using T-8 for cloning and rooting for years and they are cheap to run and replace. I just love them for that particular task. When that job is done give me MH and HPS.

it is because T5's are made for growing and give of more light in the blue spectrum and because if you are new to growing u are going to buy what u read up on or what your hydro store sells. not putting down t8's or promoting t5's just saying

Nothing wrong with a $9 or less fixture and some daylight broad spectrum t8's.

But I do like my T5's

I still use T-8's also for seedlings and cloning.

A lot of people think that T-5's are better than T-8's but it has nothing to do with the light output.

It refers to the diameter of the bulb.

T-5 = 5/8 of an inch
T-8 = 8/8 of an inch (1 inch)
T-12 = 12/8 of an inch (1 1/4 inches)

Unless it is HO or VHO then the only real benefit is that you can fit more T-5's in a certain area then you can T-8's.