This was really fun to solve! :))) Gosh, it IS my lucky day (1st try, here, too). But it's CUTE! :) If I didn't read hi19 comment, I might have much more trouble, here. :))) I somehow guessed, what he meant. :) Must be my lucky day. I got it 1st try. Found it very easy. :)
But it's a GOOD level! I see a sea-horse, when it's finished. :))) ;) Sweet! If I was a beginner, I'd get stuck here, for sure. :) Very nice use of this pattern. Makes you question where the optimizations could be at each step. Just a little inelegant overall, though. Increasingly interesting checkerboards.