how long shall i swim once?

Swimming in definitely one of the best exercises But like anythin else..Much of it is dangerous as well I guess..The max time one shud swim shud be like an hr or so..Not really much more than that I personally despise swimming coz of the Tanning effects that it has due to the chlorine in the water:(

I think swimming one hour every day is a good time to you. Not long and not short.

Swimming is very good for you, I think you should listen to your body and swim for as long as you want until your body tells you that is enough, it is a good way to keep fit.

It really takes time for you to learn how to swim with speed of course all you need is to practice everyday of you have this eagerness to learn more. I must admit that I get easily tired too if I am doing the proper strokes. Since I don't swim everyday and I can't just practice it. This sports is like a run racing too but the difference is that you are doing it on water while this running is on the air that is why it could be easy to run as fast as you can.