Leeches, aquatic nymphs (damsels, dragons, and callibaetis for example), and baitfish are good places to start. Specific patterns don’t matter nearly as much as finding active fish and putting your fly in front of them. Most of my stuff is in the size range of #8-14.
When I fish from my tube I carry one setup with a full sink (usually a type 5), and one with a floating line/indicator. I cover water with my sinking line until I find fish then try to get a bite going with my indicator setup, which is very efficient when the fish are keyed into a specific depth.
As always, read this to get your mind in the proper frame:
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