If you’re trying to decide between the 36-count or 72-count Miller Plante Septic Tank Treatment, you’re not alone. It’s one of the most common questions we get — and the answer is actually pretty simple once you know two things:
- The size of your septic tank
- How often you’ll be using the treatment
Let’s break it down.
Step 1: How Big Is Your Septic Tank?
Your tank size determines how many scoops you’ll need each month.
Here’s a quick guide:
- 500–750 gallon tank → Use 1 scoop per month
- 1,000 gallons or larger → Use 1 scoop every other week (about 2 per month)
Not sure how big your tank is? No problem. A good rule of thumb is to look at how many bathrooms your home has:
- Two bathrooms or fewer → You likely have a 500–750 gallon tank
- Three bathrooms or more → Your home probably has a 1,000+ gallon tank
It’s not exact science, but it’s usually a solid estimate.
Step 2: Plan to Use It Within 3 Years
Here’s the key factor most people don’t think about:
You want to use the entire tub within three years.
Why? Because the treatment is made with natural bacteria and enzymes. While it technically has a shelf life of much longer, the ingredients are most active and effective during the first three years. That’s when you’ll get the most benefit for your septic system.
So… Which Size Should You Buy?
✅ Go with the 36 Treatment If:
- You use 1 scoop per month
- You’re treating one home
- You want to comfortably finish the tub within three years
This is the best fit for most smaller households.
✅ Choose the 72 Treatment If:
- You use 2 scoops per month
- You have a larger tank
- You’re treating multiple homes or tanks
While the 72-count option costs more upfront, it’s cheaper per treatment — so you save a little money in the long run.
Bonus: You Get Extra Treatments
Here’s something people love — both the 36 and 72 treatment tubs actually include 6 extra treatments. That means you’re getting even more value than you might expect.
If you want to make sure you’re getting the absolute most out of your treatment, check out our guide on tips and best practices for septic care — it’ll help you stretch every scoop and keep your system running smoothly for years to come. (Link to 5 Ways to Get the Most Out of Your Miller Plante Septic Tank Treatment article)
