A waterproof, non-toxic, and reusable filter media retaining cup having molded construction, a non-compartmentalized interior space, and a perimeter wall with a preferred slight top-to-bottom taper extending between a radial flange and an opposed bottom end having spaced-apart perforations and a non-perforated center area. The outwardly-extending radial flange depends from the top of the perimeter wall and spaced-apart slits through the perimeter wall's bottom portion extend to the bottom end and are preferably downwardly-widening. The bottom end perforations and wall slits in combination with the bottom end's non-perforated center area provide accelerated aquarium water turnover through contaminant-removing filter media retained in the non-compartmentalized interior space, while avoiding clogging and channeling that would otherwise slow the breakdown and removal of uneaten food particles and marine life bio-waste in the aquarium water, which in increasing concentrations becomes toxic to the marine life in an aquarium tank depending on it for survival.

A horizontal flow water treatment method and wetland biofilter apparatus provides a chamber with impermeable outer walls spaced away from permeable interior walls of a media filtration bed such that a catch basin is formed between the outer walls and the interior walls. The catch basin creates an open area around the perimeter of the interior walls for influent water to fill within the open area before penetrating the filtration media, providing a large surface area for influent water to interact with the media filtration bed. The influent water enters the catch basin in a horizontal flow path to provide for pre-settling of particulates before making contact with the filtration media. The biofilter design increases the available surface area of the media filtration bed by up to four times for a given volume of water, and thereby minimizes the loading or infiltration rate on the media filtration bed.

The present disclosure provides an electron donor biofilm carrier and preparation method thereof. The electron donor biofilm carrier is mainly used in anaerobic or anoxic suspended carrier biofilm technologies. Electron donors with a standard electrode potential below 100 My are used as the functional material for preparation of electron donorbiofilm carrier. The electron donor biofilm carrier may contribute to the enrichment of the biofilm functional bacteria and the improvement on treatment performance of the anaerobic or anoxic suspended carrier biofilm reactor.

A method for the treatment of water, the method comprising the steps of anaerobic uptake and storage of at least a portion of the organic components in the water by a heterotrophic denitrifying biomass absorption of ammonium ions with an ammonium ion absorbent; and aerobic oxidation of the absorbed ammonium by a nitrifying biomass comprising ammonium oxidizing microorganisms, wherein the step of aerobic oxidation of the absorbed ammonium is preceded by the step of exposing at least a portion of the nitrifying biomass to atmospheric oxygen.

Provided are a water quality purification device, and a water purifier and an aquarium that use the water quality purification device. The water quality purification device includes a component filled with a micro-electrolysis catalyst and a biological filtration component that are connected in series. By utilizing a micro-electrolysis technology, pollutants in water are preprocessed and the biodegradability of the water is improved. A water body processed by the micro-electrolysis catalyst enters the biological filtration component, which can greatly improve the purification efficiency of the biological filter bed. Working together with an adsorption electrode, this structure can effectively stabilize the water quality in the aquarium and greatly reduce the required times of changing water.

This water treatment system is provided with: a reverse osmosis membrane device; a biofilm treatment device that has a carrier, on a surface of which is formed a biofilm, and that treats water to be treated before the water to be treated is transmitted through the reverse osmosis membrane device; and at least one of a water to be treated stoppage period circulation means and a water to be treated stoppage period supply means that are driven when the intake of new water to be treated is stopped. The water to be treated stoppage circulation means supplies and circulates water to be treated from a water to be treated discharge outlet side of the biofilm treatment device to a water to be treated supply port side. The water to be treated stoppage period supply means supplies new water to be treated to the biofilm treatment device.

The present invention relates to a biological filtration process for water loaded with nitrogenous pollutants in order to reduce the global nitrogen content of said water, characterised in that it comprises a first step of nitritation and filtration carried out in a first aerated biological reactor, a second step of deammonification, denitrification and filtration carried out in a second non-aerated biological reactor, and a step of evaluation of the ratio of the nitrite content to the ammoniacal nitrogen content of the water at the outlet of the first reactor. When this ratio is greater than a predetermined stoichiometry value, the process according to the invention comprises a step of addition of water to be treated to the water originating from the first reactor so as to obtain, at the inlet of the second reactor, a mixture having a ratio of the nitrite content to the ammoniacal nitrogen content that is close to the stoichiometric ratio of the Anammox reaction.

A horizontal flow water treatment method and wetland biofilter system with improved flow control via a tubular apparatus and further comprising a chamber with impermeable outer walls spaced away from permeable interior walls of a media filtration bed such that a catch basin is formed between the outer walls and the interior walls. The catch basin creates an open area around the perimeter of the interior walls for influent water to fill within the open area on all sides before penetrating the filtration media, providing a large surface area for influent water to interact with the media filtration bed. The influent water enters the catch basin in a horizontal flow path to provide for pre-settling of particulates before making contact with the filtration media. The biofilter design increases the available surface area of the media filtration bed by up to four times for a given volume of water, and thereby minimizes the loading or infiltration rate on the media filtration bed.

Methods, apparatus, and systems involving wastewater treatment systems are provided. The descriptions include a wastewater conduit with a pair of curved infiltrative surfaces. These curved infiltrative surfaces pass wastewater from within the conduit to outside of the conduit.

The present invention is a self-regenerating biofilter. The biofilter tank receives untreated water through an intake inlet, filters it through a filtration mass and expels purified water through an output outlet. The filtration mass includes gravel and activated carbon layers separated by a mesh screen. A compressed air line is located below the mesh screen. Periodically, the biofilter self-cleans by opening a flush valve that expels a flush water stream carrying debris. The biofilter self-regenerates by periodically stopping filtration for a time, allowing biological matter left on the activated carbon to degrade into biomass. Periodically, the biofilter removes and flushes out biomass by application of water or a combination of air and water.