Help!!

Need some guidance from those who are successfully managing a fresh planted
tank.

Problem: No plant growth, algae covered.

What I have: 75g 48"L x 20"H x 18 D. Flourite/gravel mixture substrate, (2)
metal halide 175w 6500k/(2) 40 w flourecent plant bulbs.

I know the first answer is get a co2 setup, but I had better luck with (3)
40w flourecent bulbs over the metal halides. Should I use a different
spectrum of light such as 10k? Surely with 350w + 80w light would be
sufficient. (doesn't look very bright, yellow tint, 6500k bulbs) The bulbs
are about 8-10 in above the surface of the water. I have no problems with
the fish stock . Can get ph, O2,CO2 readings, if needed, but I think I've
got a bigger problem. I tried adding pottasium, iron and liquid CO2 on a
regular basis, but it doesn't do anything. Any assistance would be
appreciated.