<p>Reduced operational control of wastewater treatment is expected in small communities, requiring robustness and effectiveness on the chosen treatment system. This research aimed to evaluate the treatment capacity of three systems composed of gravel #1 prefilters followed by horizontal subsurface flow constructed wetlands (HSSF-CWs) fed with university effluent, under ultrashort hydraulic retention time (HRT) and reduced operational control (in small-scale units). With unitary useful volume of 12.5 L, the constructed wetlands were batched fed with a 42&#xa0;L·d⁻¹ flow rate (HRT = 7.2&#xa0;h) and organic load of 1775&#xa0;kg_COD·ha⁻¹·d⁻¹, from plastic barrels weekly fed with sewage. The three CWs differed in vegetation cover, being one unit not planted and the others respectively&#xa0;cultivated with cattail (<i>Typha domingensis</i>) and calla lily (<i>Zantedeschia aethiopica</i>) . Physical and chemical variables were quantified by simple biweekly samplings during the 162&#xa0;days monitoring. The plant species uptake was also estimated from the dry mass of the last harvest. Despite operating in non-ideal conditions for HSSF-CWs and the cultivated plants, the pollutant concentrations were significantly lower than the inlet (average efficiencies over 68% for COD, 36% for total solids, 80% for TKN and 13% for TP). While cattail showed better initial vertical development, the calla lily showed higher productivity and pollutant extraction capacity. Standards for sewage discharge into water bodies were met, suggesting that the increase of HRT and plants’ adaptation time could lead to greater efficiencies and crop productivity, and may even result in a significant difference between the planted units compared to the control unit.</p> Graphical abstract <p></p>