You should study the life cycle of salmon for just an hour or so Linda. That's just one example of a fish, born in fresh water, which migrates to the salty sea, then back to fresh water again to breed. Most fish can tolerate brackish water for a while. Whales swim inland and are even found in rivers from time to time. If you have an aquarium with fresh water fish at home, you should always add some sea salt to it, they will be healthier. Those are all facts.

Highly unlikely organic matter would not have decomposed in a relatively short time, a few years only, in the sea. Some fish eat vegetation only, many are carnivores, even cannibals, eating their own young, like trout. If you've ever watched catfish feed you'll know them as the vaccum cleaners of the oceans, and fresh waters also. They will eatt just about anything, crabs and lobsters love to eat dead stuff.

Answer, the fish ate it up. in fact, they feasted. Have no doubt about it. The organic matter, tree trunks etc, decomposed if it didn't get eaten.

Plenty of dinosaur fossils have been found buried only a few or several feet deep, on the earth. Bones wouldn't have lasted more than a decade or 3 in the sea. If you've ever gone sea shell hunting you will know that shells that no longer contain a living creature, get worn away by the sea quite quckly. The only time you can ever really find a perfect speciman is when you find a shell that is only a few months old. After a few years of being tossed around on the floor, they get all smoothed out, they lose their points, they crack etc.

all of these things are pretty basic common and pragmatic knowledge that a lot of 12 year olds already know. I do not understand why you consistently question things that have such obvious answers. Have you never spent any time actually thinking about these questions you ask? The answers are plain as day.

there may be no evidence of a flood in ice cores because ice floats, obvious answer again, one I already gave you. did you forget already? . The rains or snows of a flood are no different than the rains or snows happening today.

I'd say most likely... parasites and the like hitched a ride on their hosts by the hundreds of thousands Linda, obvious answer again. It's the same today if a body dies... the worms don't start crawling out you know.... they eat the body. Obvious answer again.

you really need to do some thinking.

Who said the earth was overpopulated at the time of the flood? Certainly not the bible. You should read it some time.

Why do you ask the same questions over and over again? Would you like it if a student did that to you in a classroom? Probably, you'd have him him stand in the hall to do some thinking on his own for an hour wouldn't you?