Co-Owner · October 3, 2025
This Halloween Season, it’s easy to focus on scary skeletons, ghouls, and wraiths.
But if books have taught us anything, it's that not all monsters are bad. Some are just misunderstood.
Take Frankenstein’s Monster as an example. Sure, he’s a scary mash-up created by a mad scientist, but the story explores his positive traits in a meaningful way.
Bacteria are a lot like this.
When we first learn about bacteria, it's a bad thing.
It makes us feel gross, infect wounds, and in some cases, can result in hospitalizations and death.
Growing up, those lessons always came with ‘wash your hands!’ But later on, we learn there are good bacteria, too.
This October, in the midst of all these villainous themes, let's go against the grain together and explore the unsung heroes of your septic system.
Anaerobic bacteria, the workhorse
When you think of a septic system, there are several different types within that perform different functions.
Anaerobic Bacteria is the workhorse of the colony nested under your yard. It does well in places without much oxygen.
They convert all waste in layers of sludge, which sinks to the bottom, while producing gases like methane.
This kickstarts the natural process of converting your home’s output into something the ground can absorb and filter naturally.
Facultative bacteria, the shape shifters
If Anaerobic Bacteria had a family, Facultative Bacteria is the more successful older sister that grandparents tend to dote on when they’re at bacteria church.
They can live in places without much oxygen, like anaerobic bacteria, but they can also work where there's plenty of oxygen, like the leach field.
Allowing them to break down waste no matter the case. They tend to be present throughout the entire process.
The stages of the ‘haunted house’ that is a septic system
Considering what septic tanks are used for, it’s no secret that the trip waste takes is far from pleasant from the perspective of us humans.
But what are the stages of that trip?
While the process may sound scary, it’s perfectly suited for filtering our water back into our environment in a way that is not terrifying (Implying you’re upkeeping your systems).
Stage one, the flush
Food waste, gray water, and the ever-pleasant blackwater start their trip through the pipes that lead to your system.
This part is pretty self-explanatory, and you don't think about it much unless something backs up. (Eeek!)
Stage two, the settling
Wastewater is allowed to settle when it enters the tank.
Meaning: heavier solids sink to the bottom, while lighter materials, like grease and oils stay on the top, creating a scum layer.
Stage three, decomposition
Everything decays, and waste is no different. The anaerobic bacteria we mentioned get to work right away on the sludge at the bottom of the tank.
This reduces the amount of waste at the bottom, converting it to simpler substances to be further broken down and filtered out, like methane.
Stage four, scum treating
Much like a heroic cop throws criminal scum into jail after foiling their plans, so does the humble bacteria in your tank.
Tossing the materials that shouldn’t be there into a metaphorical jail of its own, breaking the criminal networks that hold the grease and fat together.
If the metaphor lost you, here's the short version: bacteria break apart the bonds that hold these fats together, turning them into smaller and smaller bits.
Side note: If there’s too much grease in a system, it overwhelms it, causing buildups.
Stage five, the release
Once the waste has been adequately treated, and the pressure and water level are just right.
The remaining liquid wastewater flows out of the tank and into the leach field.
If we follow the metaphor from stage 4, the ‘reformed robbers’ are released into a drain field.
Stage six, bacterial probation
Because the ‘cops and robbers’ costume on this process is fun: Consider the leach (or drain) field ‘probation’ for the released bacteria.
The final step for the wastewater until it can ‘integrate back into society.’
This is the end of the line.
Don't slay these monsters: how to protect your septic bacteria
To protect these little guardians, remember a few tips:
Avoid antibacterial products. They kill the good bacteria along with the bad.
Don't dump harsh chemicals. Bleach, ammonia, and drain cleaners can wipe out your microbial workforce.
Use septic-safe cleaners. Pick products labeled “septic safe” or biodegradable. (See our suggestions.)
Looks can be deceiving
So this Halloween, while you're dodging jump scares and watching creature features, remember: not all monsters are out to get you!
In fact, the beasts lurking in your systems are actively working to protect your home from real horrors: system backups, sludge overflows, and costly repairs.
So this October, remember to give a little thanks to the misunderstood creatures down below.