South Florida is definitely challenging at times for soaps. LolI also live in South Florida and I have learned a few things because when I first moved here, I got DOS several times. I now always use distilled water, not tap, make sure to cover any racks, even if you think they are coated, also cure away from Sunlight (of course we live in AC year round), I also use citric acid (which reacts with the lye to form sodium citrate, which is a chelator). Adding a chelator helps a lot, I also add EDTA to every soap, and since I have been doing this I have not experienced DOS.
We were not using distilled water but clearly that is a must. A lot of people have told us that.
We were using 38% at first and one of the things I didn’t like was how much smaller the final bars became after curing, and some times they would get concave Like the image attached, of course not as much but with too much water, when they cure the shape changes a lot.@DeeAnna, I completely disagree with using 38% water as a percentage of oils. First that is a lot of water - way too much for cold processed soap, this was originally meant for hot processed soap. Second, it's a better idea to relate the water to the lye, since water has nothing to do with oils, and everything to do with lye. I personally use 1.6:1 water to lye ratio, but for some soaps that are higher in liquid oils, I use 1.3:1. Third, using a ratio or even a lye concentration is better because you get more consistent results. With 38% water as a percentage of oils you can get an unstable emulsion, (particularly for new soapmakers who can't spot emulsion), glycerin rivers and soap warping because of the great amount of water loss and lots of soda ash.
We’ll try with 1.6:1 - thanks for the tip and for sharing all your knowledge.