Yes. Or you could get a simple, new OTO/Phenol kit. If you can, try to find one that goes to 5ppm not 3. Leslies stores sometimes sell the Taylor version of the OTO/Phenol kit, the K-1000 and that goes to 5. If the phenol red reagent is the R0014, that's even better as it neutralizes chlorine and allows accurate readings when the chlorine is higher (Higher FC levels cause pH levels to read higher than they really are).