Macrospilota
I kept two turtles in a tank with the water that just covered their shells. There was no substrate and they flipped over while trying to get out and drowned because the water was not deep enough to allow them to turn over and too deep to let them breath without flipping over first. I lost a few in the past behind filter tubes as vickie almost did. I have had them get pinned under rocks, and get caught between the glass and driftwood. I have had them get to cold then not be able to swim and drown. I have had them get their heads, limbs, or shells caught in various high volume pumps that had the pickup screens knocked off. I have had one male spotted drown another out of aggression. I have frequently brought them back, but sometimes they have serious brain damage and will not ever function and die a few days or weeks later. I have tried all the previously mentioned techniques for resuscitation plus some others and can relate to each individual’s circumstance. You see a lot when you have studied as many chelonians as some of us here. bbm