Hello Henry, I have an old bathtub that really needs to be recalked. There seems to be a lot of black fungus and I have to do this job myself. I am concerned about making a real mess of this job, because everyone tells me that you have to keep the line as neat as possible. I am assuming that I have to use a anti-mildew product silicone that will stay pliable. How long does the tub have to be dry for and how long after I do this job do we have to not use the tub. I have also heard that you should put water in the tub to weight it down. Any suggestion. I am absolutely green (that is not experienced) about this repair. Thanks for any help you can give me. Louise