Thanks Jeff for the confidence boost, I'll be sure to stay in fresh water!

Do you have top seat or in seat kayak? Is it inflatable? Mine is a sit in inflatable.
My problem is that I am fat (275) and stiff. My two man kayak for me is a one man one. The little seat that came for the front man is totally worthless to me, even if I try to use it in the back against the inside of the back tube. I'm better off sitting right up against back of the tube. But I still lean backwards more than I would like. And with me in the very back I sit low in the water while the front is a little high.
I thought about sticking some weights in the front, but that would negate the whole purpose of buying a kayak. I have a john boat but was invited to go on these turtle trapping and tagging trips on the Sabine River (here in North Texas it's like a big slow moving green water creek, at the gulf it is a ship channel)for a researcher at UT at Tyler. Where they get into the river you would have to drag a john boat up a large high brim and then down into the water and once you get into it you have to drag whatever you are in across or around log jams and such. So the reason inflatable kayaks are the transport of choice is because they are so light. If I stuck fifty pounds of weights into the nose I would turn my thirty something pound kayak into a 80 something pound kayak.
Really what would help I think is a light weight seat that would stand up above the back tube of the kayak and help me sit more upright. If I could get one in the middle of the kayak where the useless for me seat goes it would be even better, then I would have a better center of gravity.
But I spent a lot of time online looking for a seat to put into a sit in kayak that could be strapped on or secured some way to support my back. But the only ones I came across were for sit on top kayaks. And there is no way I can sit like an L, I have to cross my legs.
I can get by the way it is now in the back. There is no way I will stay dry anyway because we will be getting in and out all the time collecting traps so I may have to live with it. All this will end by the end of this month. And I probably won't use it again until warm weather returns. So I can live with if I have to, but if I could improve it, it would be a nicer ride.
Other than the above I really like it. It's fairly fast, responds quickly and is super quiet, and not much effort is exerted in propelling it. I know next spring and summer I will use it a lot. Be a good grandkid toy on my pond too, in fact quieter to fish out of on my pond than the jon boat, just not as comfortable and roomy.
But got any ideas for a fat, stiff kayaker?

Thanks,
Bill