I agree with GT, the sand does look a little deep; but, photos can be deceiving. Do you have any measurements of how deep it? IMO 10 days is pretty short to truly tell how plats are doing because they are going to be going through shock for at least a week or more depending on the plant. Also, HC is a notoriously slow grower and a medium pace grower in IDEAL conditions so it's not too surprising it hasn't "taken off" yet. Personally, I would monitor the tank for another week and make another assessment then.
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