If your tank is a 35g hex, then it would be 24" tall. I'd consider your light to be very weak without knowing more about the Walmart LEDs (but then again its walmart). If you're really serious about growing corals, we can give you cheap options of LEDs that can penetrate a 24" tall tank, which would cost a little less than $200. You could also consider T5 (a lot stronger than T8) and metal halide light fixtures. The taller your tank, the stronger your light needs to be. You might
be able to grow some corals close to the top of your tank with your current lighting.
Edit: the t5 and metal halides wont penetrate the height of your tank as much as a good LED
fixture with a low numbered optic (i think around 60-90 degree optics).