Aquarium photoperiod wrt ambient room light

[Winters]

Hello! My 90g aquarium is in my living room, placed next to the inside wall, facing outside windows. Even though the aquarium isn't very close to the windows, there is significant ambient light in the room during daytime. Should this affect when I have my MH's on? Can I reduce the amount of time that my lights are on due to the natural light? And will this natural light lead to increased algae levels or fish being confused due to the elongated photoperiod?

Thanks in advance.
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Imran, in Edmonton, Alberta