Soaking seeds in a glass of water before planting helps, but leaving them in for two days drowns the embryo. Twelve to twenty four hours in room temperature water is enough to soften the shell and start the process, after which they go into a towel or medium, and anything still floating at the end is not automatically dead. Soak times for fresh versus old regular seed, plus the case for a drop of peroxide in the water, appear on https://breederregularseeds.com. Longer is not better here.