Red worms, blood worms, and midge flies are a normal and occasional nuisance to wastewater operators as they tend to feed off the nutrient-rich mixed liquor, but what does an operator do with tubifex worms? Tubifex worms, aka sewer worms, are not often seen in wastewater plants, but when they are, they end up clogging filters and eating bacteria and other proteins.
Tubifex worms are very difficult to get rid of, but possible. Aquafix has recently helped a plant with Tubiflex and red worms clogging their filter system. This municipal treatment plant in Rhode Island has a 1 mgd RBC, that is followed by three sand filters for up-flow nitrification and down-flow denitrification. The sand filters are approximately 20’ by 12’ by 8’ of sand. The Aquafix team came up with a two-part plan to kill both types of worms and clean the filters of excess sludge and proteins.
Part 1: SeClear® and Qwik Zyme P
Aquafix uses a SeClear®, a chelated copper, to kill the tubifex worms, but not harm the good biology. Qwik Zyme P, an enzyme based product, is used that will break down the food source that the worms have been living on. The operators let both products soak for 24 hours and then backwashed to the head of the plant.
Part 2: AQUABACxt
After backwashing the SeClear® and Qwik-Zyme P, the operators waited two days and then added in each sand filter. AQUABACxt is a biological larvacide that contains a species called bacillus thuringiensis that kills red worms. They let that soaked 24 hours and then backwashed to the head of the plant.