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I would. Just hit it with a magfloat and be done with it. If it doesn't come off easily, it is coraline algae. At that point, I wouldn't worry about it. In my 36 gal I have the sides and back covered in green coraline.
Great looking tank!! With the goby/shrimp pair you're going to want to make sure your rock work isn't on the sand, but rather placed on the bottom glass. You may already know that, if so, sorry for the redundancy.