Provent-a-Mite is great. I used it once about 3 weeks ago, and I have not seen any mites or mite evidence since. Mine was not that bad of a case, but I still may retreat when I clean the tub entirely again. I use a bleach solution. I spray everything off with the detachable shower head, then fill the bathtub with warm water and add the bleach. I let everything soak a bit, then spray everything off, and draw a cold tub for rinse, get everything in it and drain it out as i tip stuff around to get all the water off. After that, as I take things out I give them a very generous spray down to make sure all the bleach residue and smell is gone. I smell everything once I have it all sprayed off (a couple of towels on the floor works fine), and if there is no bleach smell, I let it drip/air dry for about 10 minutes then I wipe everything down with a dry clean towel. If it still smells like bleach, everything gets another spray down and I repeat the process.

I have only had my bp long enough to have to do 1 cleaning, but it only took probably 3 rinses total to get the bleachiness off.

Good luck.