I have a Koi fish that has a light pink almost growth like on its right side and was wondering if anyone could help me out and give me some advice on what it could be.? Thank You!

Can you describe it more or post a photo? It might be an injury, a cyst, carp pox (a virus), or some sort of tumor (benign, bacterial, etc.). Are you sure it's not a fish louse? They aren't normally pink but can be clear or brownish. I hope it's nothing!