How long will it take you to drive from where you are to where we are? There are a lot of variables there to deal with, so it is hard to even give a guess without better information. One thing is certain, if you get in your car and start heading for Phoenix Arizona right now, you are going to get here faster than if you wait for all the information. The same is true when trying to guess how long it will take to clean up the sensors on a RV holding tank. The answer could be anything from they cannot be cleaned, it is broken to they will clean overnight. All kinds of conditions and variables are going to affect the cleaning time. What chemical was used previously? What is the shape and depth of the tank? Is there a belly in the tank? Is the RV always in one place or is it moving and how far and how often? Is the mother culture being held in the tank or is it being emptied completely? There are as many variable combinations as there are RV’s. The only thing that is certain is when you add TankTechsRx to the holding tank, the probiotic mother culture will be cleaning the holding tank 24/7 as long as there is water in the tank. We wish we could be more specific on timing but there is no way to predict. We only know it will happen because that is what TankTechsRx does.