Not weeks... but he is more lazy than he was when I first got him overall for sure. You know, you just don't get polys for tank movement.
Except maybe Sens and Pollis.
Not sure re: brown sand. Maybe CaribSea? If you have black you might just try it and see.
Soba is definitely greener and has more contrasting patterns than your not-named-PLANTFACE Moke. But I'm not sure how much is substrate vs. individual fish.
Cohazard
would be a great resource on that topic as he has a bunch on the same substrate, but I haven't seen him around much lately...
Soba's most recent pics. Of course I've also had him a lot longer and he is well established in my tank. He's around 8" or so, haven't measured lately.