It’s early morning and you just took a sample of your sludge from the aeration basin, after a few minutes you notice your settleometer isn’t looking how it should.
You notice the water is looking slightly cloudy and light in color
Next
Protecting your bugs
A scenario based simulator to for water operators to help them in identifying and maintaining the population of bugs in their aeration basins
Start
How are you going to fix this problem?
Option 1
Option 2
Option 3
Check your Biological Oxygen Demand (BOD) levels on the influent, to verify if there is enough food for the bugs.
Feed the bugs in hopes that they mature and reproduce on their own.
Take old sludge from the digester and seed it into the aeration basin.
+ INFO
+ INFO
+ INFO
You decide to check the Bod levels
Your plant's typical BOD levels are around 150 milligrams per liter. But when you check your levels they...
are high
are low
Your levels are reading around 250 milligrams per liter.
Your levels are reading around 80 milligrams per liter.
+ INFO
+ INFO
You decide to check the Bod levels
Your levels are reading around 80 milligrams per liter. What is your best course of action?
Open the blowers and add more dissolved oxygen to the aeration basin
Turn the air down
+ INFO
+ INFO
You Open the blowers and add more dissolved oxygen to the aeration basin
Great job, now the bugs are more active and they are treating more of the excess BOD (food) that is within the influent.
Back
You turned the air down
Unfortunately the bugs are now showing signs of less activity, the proper 85-95% BOD removal is not being met. This could put you in violation of your state issued permit.
Back
You decide to help nature propegate faster by feeding the bugs
You have two options of how to introduce food to your aeration basin. Do you...
add bio-augmentation
Add dog food
You've overheard some of the veteran workers mentioning putting dog food in the aeration basin. Maybe you should give it a try.
You've always been one to try out new technology, and decide to add the manufactured bio-augmentation.
+ INFO
+ INFO
You sprinkle a bag of dry dog food into the aeration basin
You have created a higher BOD level and if you added too much it could create higher than allowable permit levels. But you have promoted the propagation of the bugs. Your tests will come out worse but it will level out and within a few days you have a healthy bug population.
Back
You decide to use bio-augmentation
This could decrease chlorine levels, possibly dipping below 1 miligram per liter which could lead to being out of permit. You will need to adjust the rate of chlorine feeding into the final effluent so that you are within 1 to 4 miligrams per liter range of chlorine.
Back
You decide to seed the aeration basin with old sludge
You begin sending the old sludge into the aeration basin from the digester. But how much do you let go into it?
a little bit more
As much as possible
Just a little
Introduce 1,000 mg/L of old sludge.
Introduce 3,000 mg/L of old sludge.
Introduce 5,000 mg/L of old sludge.
+ INFO
+ INFO
+ INFO
You Introduce 1,000 mg/L of old sludge.
You still have insufficient amount of bacteria for the incoming BOD, you will still have turbidity (cloudy) water and poor nitrification levels.
Back
You Introduce 5,000 mg/L of old sludge.
You have now introduced too much old sludge into the aeration basin causing bulking sludge (poor settling in your clarifiers) and will lead to poor quality effluent. You will need to waste the excess sludge out.
But by wasting you reduced the number of old bugs within the aeration basin and new bugs, however we also introduced other types of bacteria that are not as desirable for operations of the plant such as filamentous bacteria causing slow settling flock which hinders treatment.
Back
You Introduce 3,000 mg/L of old sludge.
Congratulations! You check the settleometer again after 45 minutes and you have a clear supernatant.
Back
It’s early morning and you just took a sample of your sludge from the aeration basin, after a few minutes you notice your settleometer isn’t
Christian Johnston
Created on October 18, 2025
Start designing with a free template
Discover more than 1500 professional designs like these:
View
Animated Chalkboard Presentation
View
Genial Storytale Presentation
View
Blackboard Presentation
View
Psychedelic Presentation
View
Chalkboard Presentation
View
Witchcraft Presentation
View
Sketchbook Presentation
Explore all templates
Transcript
It’s early morning and you just took a sample of your sludge from the aeration basin, after a few minutes you notice your settleometer isn’t looking how it should.
You notice the water is looking slightly cloudy and light in color
Next
Protecting your bugs
A scenario based simulator to for water operators to help them in identifying and maintaining the population of bugs in their aeration basins
Start
How are you going to fix this problem?
Option 1
Option 2
Option 3
Check your Biological Oxygen Demand (BOD) levels on the influent, to verify if there is enough food for the bugs.
Feed the bugs in hopes that they mature and reproduce on their own.
Take old sludge from the digester and seed it into the aeration basin.
+ INFO
+ INFO
+ INFO
You decide to check the Bod levels
Your plant's typical BOD levels are around 150 milligrams per liter. But when you check your levels they...
are high
are low
Your levels are reading around 250 milligrams per liter.
Your levels are reading around 80 milligrams per liter.
+ INFO
+ INFO
You decide to check the Bod levels
Your levels are reading around 80 milligrams per liter. What is your best course of action?
Open the blowers and add more dissolved oxygen to the aeration basin
Turn the air down
+ INFO
+ INFO
You Open the blowers and add more dissolved oxygen to the aeration basin
Great job, now the bugs are more active and they are treating more of the excess BOD (food) that is within the influent.
Back
You turned the air down
Unfortunately the bugs are now showing signs of less activity, the proper 85-95% BOD removal is not being met. This could put you in violation of your state issued permit.
Back
You decide to help nature propegate faster by feeding the bugs
You have two options of how to introduce food to your aeration basin. Do you...
add bio-augmentation
Add dog food
You've overheard some of the veteran workers mentioning putting dog food in the aeration basin. Maybe you should give it a try.
You've always been one to try out new technology, and decide to add the manufactured bio-augmentation.
+ INFO
+ INFO
You sprinkle a bag of dry dog food into the aeration basin
You have created a higher BOD level and if you added too much it could create higher than allowable permit levels. But you have promoted the propagation of the bugs. Your tests will come out worse but it will level out and within a few days you have a healthy bug population.
Back
You decide to use bio-augmentation
This could decrease chlorine levels, possibly dipping below 1 miligram per liter which could lead to being out of permit. You will need to adjust the rate of chlorine feeding into the final effluent so that you are within 1 to 4 miligrams per liter range of chlorine.
Back
You decide to seed the aeration basin with old sludge
You begin sending the old sludge into the aeration basin from the digester. But how much do you let go into it?
a little bit more
As much as possible
Just a little
Introduce 1,000 mg/L of old sludge.
Introduce 3,000 mg/L of old sludge.
Introduce 5,000 mg/L of old sludge.
+ INFO
+ INFO
+ INFO
You Introduce 1,000 mg/L of old sludge.
You still have insufficient amount of bacteria for the incoming BOD, you will still have turbidity (cloudy) water and poor nitrification levels.
Back
You Introduce 5,000 mg/L of old sludge.
You have now introduced too much old sludge into the aeration basin causing bulking sludge (poor settling in your clarifiers) and will lead to poor quality effluent. You will need to waste the excess sludge out.
But by wasting you reduced the number of old bugs within the aeration basin and new bugs, however we also introduced other types of bacteria that are not as desirable for operations of the plant such as filamentous bacteria causing slow settling flock which hinders treatment.
Back
You Introduce 3,000 mg/L of old sludge.
Congratulations! You check the settleometer again after 45 minutes and you have a clear supernatant.
Back