Chlorine is best. Lots of people used lots of different things and it just didn't work to effectively keep the pool clean. One customer insisted on using bromine (and always had a ton of people over her pool) but every time we came, we had to shock the pool with chlorine shock to knock it back into shape. We just didn't tell her because she was an idiot who couldn't be reasoned with. Chlorine is simply the best chemical for pools. If chlorine bothers your skin (and even if it doesn't) I recommend using a
Nature2 with chlorine. The Nature2 allows you to run your pool with very little chlorine. I used to lifeguard and we kept public pools at a 4.0 level of chlorine. Private pools without a Nature2 should be kept between 1.5 - 3.0. With a Nature 2 you can keep your pool at a 0.5 chlorine level. You can also get one for the
spa. I use one in mine and my skin is very sensative but the pool hasn't bothered it in years.