Tube jigs are a mainstay when running floats in the Midwest. One of the best producers is a white tube jig (crappie size) tipped with a couple of wax worms or a 3-4 egg spawn bag. The tubes seem to work the best when the water is very cold and clarity is good. We fish the deepest, slowest frog water we can find (cold weather holding water), and use very light line and leaders. The fish have lots of time to look over your gear, so it's an absolute finesse gig. Typically, the jigs are 1/16 and 1/32 ounce, and staggered split shot on the line to make the float very unstable.

Other colors that work well are hot pink, black, and occasionally chartruese, in that order. I usually try to shoot a little smelly jelly or scent (Dr. Juice) up in to the body of the tube.

There is no reason that a 1.5 or 2 inch tube wouldn't work for nates. The guys over in Ohio and Pennsylvania were doing really well on 1" black berkley Power Craws last winter. Haven't tried tham yet, but I'm going to.

The above methods may be worth a try on those spooky clear water summer runs you have. Good luck and hope this helps.