The light will help them grow, just like any seedling.
What species are they? Aponogeton, Crinum, or Nypheae?
Also, they often have a guarantee to replace any bulbs that don't sprout. If they don't sprout, take them up on the offer!!!! I've always had dud bulbs replaced by those companies like 3 to 1! I've bought dead dried bulbs from the pet store knowing that I can return them to the company and get about 3 times more!
Good Luck!
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