We imagine you would like to know how long it will take TankTechsRx to make a difference in the holding tank? To be honest we can’t say for sure because we do not know what is in the tank or how bad it is. Everett’s experience in the accompanying video is fairly typical, but every tank is different. What we can say for sure is that the tank is getting cleaner and cleaner every hour it is in there. The mix of probiotic microbes were blended in a patented fermenting process that teaches them how to cooperate with each other and outcompete the harmful odor causing bacteria in the tank. They will reproduce at a rate of up to 19 billion to one every 12 hours. It could take up to 3 days to grow enough to capture the entire tank, but once it does it will keep that quorum as long as it is not flushed out completely and the maintenance dosage is added after dumping. There should be a detectable difference within the first 12 hours in most cases. In some cases, the original dose of two ounces may not be enough because of the conditions in the tank. In that case just add one more ounce to take it over the top. Most of the other products us a deodorant that gives an immediate sense of relief, but the problem quickly returns. TankTechsRx does not use any deodorant. We rely on the process described above to permanently fix, not just band-aid the problem. If odor is a serious issue add a half ounce of TankTechsRx to a 16 oz spray bottle and use it to spray the air and directly down the toilet while flushing. It will remove the odor for a while but will have to be reapplied until the probiotics capture the entire tank with a mature mother culture. The product was NOT designed to do this, but it will work. Our science department is developing a ready to use spray specifically to control odor. Check the product page. It might be there by the time you read this.