Not sure how to actually test oxygen levels under the thermocline but my guess is there isn’t. Very rarely do you mark fish under it and the ones that occasionally are I believe are hybrid chasing wounded baitfish down and coming right back up. I’ve used some weightless wacky rig stuff and it works marginally. Top water bite is scarce for some strange reason, my guess is due to the huge amount of pressure the lake gets. Everybody and their brother is throwing a popper right off the rip. Just sets up very odd when it gets hot out, they don’t school and are very hard to pinpoint almost as if they are just cruising the entire lake constantly. Left my flukes at home last time they will be going back next time to see how that goes. They also seem to really key on the very small baitfish over the bigger shad when it’s hot as well so may try some smaller fluke style deals.