Aim of the study:
Adaptation of MBBR technology for the treatment of highly degraded waters in small water reservoirs. Investigation of the effectiveness of organic pollutants treatment in waters with highly polluted municipal sewage (or easily biodegradable). Checking the effectiveness of nutrient removal during the process of cleaning this type of pollutants.

Material and methods:
The study were conducted in laboratory conditions on a technical quarter scale. Diluted municipal sewage was treated to determine the purification efficiency for each laboratory stand. The experiments were carried out in 4 research stands (Volume of wastewater in each tank were 1000 L), each was equipped with a MBBR bioreactor with moving bed (biofilm carriers) . The physicochemical parameters of pH, redox, oxygen concentration were examined and laboratory analyzes were performed to indicate changes in COD, BOD5, and selected forms of NH4 and PO4. On the basis of the obtained results, the effectiveness of the wastewater treatment was demonstrated and the hydraulic parameters of the installation were modeled.

Results and conclusions:
The results of experimental work indicate a significant effectiveness of the process of purifying and removing nutrients in MBBR installations. After designing a suitable floating platform, it will be possible to introduce such installations into degraded water reservoirs for their purification.