Dap Quik Seal does mold underneath & rather quickly too! It is pretty dry in CA. but molds anyway & I'm replacing it almost on yearly basis. Used to last a couple of yrs. Tried the more expensive gold label Quik Seal Plus & didn't notice any difference besides price! I use it as at least you can dig it out! DD has stuff that forms a plastic like impossible to remove line that also molds & can't be cleaned I went over it with the Dap Quik Seal, looks better. I imagine they took out something to "green it up" so reason it no longer works for very long.

First of all, thanks for the input on the clear silicone - on my most recent install (today), I will not use it around the toilet base. I have installed 3 new toilets in the last 18 months in our house, leveling the floor in 2 cases. In all three cases the new toilets sat flat as a board on the floor - because the floor was flat; you can dry fit the toilet before you put in the wax ring to test it out. I'd absolutely return a non-flat-bottomed toilet - no shims for me, please. I personally like the no-caulk look though it's not to code, but in this last install, the toilet is right by the tub and I will go with a thin bead of white caulk to prevent the situation below: I remember staying in a new apartment abroad, and they had a sink that sat flat on the counter with no caulk around it. Water from the shower would get under the sink, and if you blotted up the spill, you'd also pull black moldy water from under the sink - one good reason to caulk a toilet right by a shower/tub - water getting in a crack doesn't mean it will dry out quickly. cconlin, I feel your pain. Some clear silicone in our shower has been going strong for 28 years - but a couple of bottom corners of fairly new silicone get mildewy within a couple of years. Sadly, you're just going to have to use something like a 5-in-1 tool to scrape off as much of the caulk as you can, then mineral spirits to remove the remaining residue. Then re-caulk. There are sprays to prevent mold in the shower, but if mold is there already, it won't come out. Note that siliconized acrylic/latex caulks or plain acrylic/latex caulks are easier to remove so if you match your grout instead, you can redo the caulking with less effort though they tend to mold more quickly.

First of all, don't use bleach. Bleach will not kill established mold. The properties of bleach don't allow it to penetrate into porous materials...the water that carries the sodium hypochlorite (the actual "bleach") will penetrate, but the chlorine will not. Household bleach is essentially 94% water and 6% sodium hypochlorite, so straight out the bottle or diluted, your killing the surface mold but feeding it's roots when the water saturates the material. For mold, use a quaternary ammonium chloride product like Shockwave. IF the mold is deep-rooted in difficult materials, it might take a couple of applications. As has been mentioned, some of your other staining looks like iron build up, you can use a product like Iron Out, or a product like CLR. It might be that the plastic itself is stained, so treatment may not be satisfactory. You can unscrew the shower head (or handheld unit as a whole) and soak it in CLR or Iron Out. That might dissolve and clean off some of the discoloration. You might have hard water deposits on the metal. CLR should help with those. Or use a bit of vinegar. Vinegar is a mild acid that might dissolve those mineral depostis, if that is indeed what they are. Older jetted tubs tended to hold water in the plumbing pipes after the tub had been drained, so there may be some nasty stuff within. You could fill the tub with hot water, run it, let it soak, then add Iron Out and/or Shockwave or a commercial jetted tub cleaner to the same water, run it, let it soak, run it, drain, refill with clean water, run to rinse, drain, and see if that helps. Mold spores are everywhere. EVERYWHERE. They'll thrive in the correct environment. Cool, moist, etc. You can take away the "moist" with effective bathroom ventilation. Good luck!

We are doing a product from Sentrel aka Flexstone. It is very nice looking and easy to work with. Our shower is 48" wide by 34" deep (the pan). We got the 96" tall panels to go to the ceiling and their 48" by 36" kit along with their upgraded niche with a shelf and corner seat. The corner shelf came with the kit. There is also trim for the top and sides. We are only going to use the side trim and just caulk the top to the ceiling. All in with swanstone pan, new trim, grab bar, shower head and Sentrel aka Flexstone we expect to be about $2K for a DIY. They have an installation locater on the web site. Don't know how much it would be to get installed. https://www.sentrelproducts.com/ It comes in alot of different patterns. We are almost done but have been hung up by an odor from the drywall work that was done and are waiting for some sealing primer to try and eliminate it before we get to final trim and paint. They give you corner seams that you glue in place before placing the panels so that there is extra water proofing behind the corners. I have a thread that shows all the details of the kit if you are interested. https://www.houzz.com/discussions/5918286/flexstone-sentrel-panels-calacatta-white-pictures#n=9