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Laboratory + Get AlertsWhen you think about it, we're looking into another world when we grab a water sample, place it on a slide and zoom in. The microscope is one very cool piece of equipment, and you'll usually see one in almost every wastewater treatment plant lab off in the corner — covered and waiting for someone to lift off its cover and go exploring.
The microscope is a powerful tool for wastewater operators, and I’m not sure everyone takes advantage of it. I love to grab an RAS sample and set it up on a slide and really go through it from top to bottom and side to side. I’m always searching for interesting organisms, but I'm also looking at how they live and what’s affecting them. We can't control what comes into our treatment plants, so we have to be on high alert to protect our little friends who are doing the work.
Everything you see when you set up a slide is important, including the movement of microorganisms and the shape of the floc. I like to look for filamentous bacteria, which indicates how floc is settling. Sludge age is also important to note.
Generally, in wastewater plants we look for the main characters in each type of microorganism, including bacteria, flagellates, amoebae, free swimming ciliates, rotifers, filamentous bacteria, and higher invertebrates such as nematodes, water bears and bristle worms. Each one is an indicator, telling us if we have old sludge, young sludge, no dissolved oxygen or too much dissolved oxygen. Some microorganisms even tell us when we’ve had a toxic load dumped on us.
Having a good chart next to your microscope and a checklist of what you see is very important. I like to have a checklist that includes 30 days of microscope review. It does not have to be fancy; it just has to show what you’ve seen. So, if you need to, you can go back and review previous days to understand if you are trending one way or the other.
Remember, you control what microorganisms live and thrive by controlling the wastewater environment. You are the one who controls variables such as wasting, detention time, dissolved oxygen and pH. If your plant is having trouble, you can change the growth environment and create a place for the correct microorganisms to thrive.
So get back in the lab and find your new friend over in the corner and get reacquainted. Look into the little world you’re controlling!