lighting.....

[systemfan15]

http://www.drsfostersmith.com/produc...d_op#br#ed_cl#
#ed_op#br#ed_cl#
if i would get the 48" 216 watt shown in the site above...would i
be able to just get a glass cover for the tank and put the light on it
so i wouldn't have to get a canopy??#ed_op#br#ed_cl#

[davejnz]

That is a fixture and the legs should sit on the top sides of your 4' tank(75 gal) .There is no need to put a glass cover or anything between the bulbs and the surface of the water.Not only does glass block some of the light/PAR,it also prevents good gas exchange at the waters surface.
That fixture isn't too bad but the relector isn't nearly as good as the CV retro,the endcaps are also cheap(non waterproof sockets)thats why they are selling the fixture wth a splash guard(light blocker).
IMO,I would go with the CV retro as it seems to have higher quality components(individual parabolic reflectors,waterproof endcaps,and there customer service is top notch) david@coralvue.com
FYI,I built my canopy to house my flourescents for under $20(8' of 1x6 pine and a 36x12.5" piece of 1/2" pine).If you need plans for one that'll fit your tank,LMK