After two years of work, the project "Research and experimental development of an indoor air biofilter system based on the principle of bioremediation" has been completed. The research is compiled into six scientific publications. They cover a wide range of scientific fields - plants, microorganisms, substrates, biotechnology and air quality. Publications are about the activity of microorganisms in a biofilter; on the ceramic substrate, its microbiological activity and purification potential; for root microorganisms in the biofilter; on the interaction of mineral supply and plants in the conditions of biofilter; on the efficiency of the biofilter under laboratory conditions; and the impact of biofilters on the indoor environment. Over the years, a lot of data has been obtained on the optimal components of the biofilter - which plants, ceramic granules and mineral supplies to use in the biofilter. We have practically found out how to maintain a biofilter for long-term operation. The obtained data on the effect of the biofilter on the relative humidity in real conditions show that there is a 13% increase in relative humidity; and experimental conditions show that the biofilter models are able to purify an average of 33% formaldehyde in the passing air, which increased to 46% in the water mint version. As a result of our work, we have created an efficient and aesthetic botanical air biofilter, which is based on extensive practical research and which we can safely say - it helps to improve the indoor environment.