If the baitfish are bigger in your lake go up to the 250, if they are smaller stick with the 175. For me, I try and go just a tad bigger than the forage around. As water clarity goes, if the clarity is low year round, the fish are probably adapted to finding bait in those conditions, so natural baits would work. Compared to a crystal clear lake that looses tons of visibility when it rains, that is when I would use more bright colors. Around me, water usually has less than 6 inch of visibility and natural baits work well for me since the water is murky year round and the fish I believe are accustomed to that.