Aquarium Light PWM With Arduino

I have recently converted my aquarium lights from fluorescent lighting to LED lighting and I have decided to try and simulate a natural environment where light gradually increase from dawn till midday and then decrease till dusk. At night there’s little light usually given by the moon.
Basically the LED lighting is powered from a 12V power supply and arduino controls the intensity of the light by modulating the voltage with the help of a n-channel MOSFET (I have used an IRFS630). The arduino can be powered by the same power supply but I have used a separated 5V USB PS for arduino and powered it through USB not through Vin.
The light intensity might not be the most accurate but it’s the best I could think of. The pattern can be modified through the code.”

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