I decided to try some bath fizzie tablets. I have made the bombs before, and can't get them to work well for me. So, I got the PVC pipe, the dowel. They are smaller around, but I figured that I could make them longer, no problem. So, I make them with the castor oil recipe that i found on here, scented Mango Papaya from Peaks. Colored them pink, they are gorgeous. I think ,okay, I will put them in the oven, on warm for a while. I have the air going, to control the humidity. So, I leave them in there about 30 minutes. They still seem great, no puffing, so I think, okay, I am ready to go to bed, so I take them out, place them on the table. Air conditioning gets turned off. I wake up this morning, and the tablets have puffed up out the ends, where they weren't as dried out, I guess. The sides are perfect. I will have to take a pic. They were beautiful, now they are ruined. I am so p#(*ed off. How long can you leave them in the oven for to make sure they are dried? I just had it on warm, less than 200 degrees