whats the best i want it diffused but whats the most confusing is the blocking of uv to 380nms to help stop mold but i thought uv's give a better productwhats the best choice?

bubblewrap

UV open is good for flowering plants.
Bubblewrap won`t last as long as proper greenhouse poly although some do use it inside the glazing. If its a polytunnel you`ll be hard pushed find a sheet of bubblewrap big enough to cover it in one hit

The one you want is "Sunmaster", can`t give you a link (forum rules) but its easy enough to find, and fairly cheap £5.25/m at 7.3m width.
Total light transmission in the 400-700 nms as % 88%
Average % of Diffusion in the 400-700 nms as % 60%
UV transmission from 300-399 nms Open

was thinking off

Luminance THB AF 800 gauge. Providing diffused light at 90% to increase growth and yield, Infrared solar radiation is screened out to keep the environment cooler without a similar reduction in photosynthetic radiation. An anti condensation additive is applied to the interior surface of the film and the cloudy finish to this material helps reduce scorching on hot summer days. With a high light diffusion this film is recommended for a variety of crops especially nursery stock, ornamental / bedding plants and strawberries.

light Transmission


Light Diffusion


Thermic
Effect


Thickness
Microns


Yield
Strength


Fold Impact



Politherm AF


90%


22%


82%


180


7.5 MPa


>550g

Luminance THB


87%


>90%


88%


180


7 MPa


>550g

Anti-fog isn`t all its cracked up to be as it wears out after a year.
I noticed at the end of the spec they say, "Note, however, that spring growth may be earlier under Politherm"
which seems to suggest you may be better off using a different film if light levels are a bit iffy.

being that sumaster is thinner does this make a difference and spring growth is bad?
also thanks for the help

Its made of M-LLDPE which makes it stronger than thicker stuff made of LLDPE, but its no cheaper as the additive is expensive