I never have had to do such an extensive SLAM. I'm hopefully towards the end of it but now having tested and retested so many times I ran out of my last bottle of R-0871 much faster than I thought I would. I didn't see it coming since it took me 2 years to get through the first one. I used 66 drops tonight and don't think i'll have 66 drops tomorrow morn to do the OCLT. should i run to the pool store for a chlorine tester? even, now, with amazon prime I probably couldn't get something until monday. I know there's another kit folks seem to like on this site. maybe they have faster shipping than TFTest kits? thx