Abstract: Mussels and related bottom dwelling creatures may be eliminated from an underwater bed by applying to the zone of at least the bottom 2 feet of water above the bed water-soluble sulfite salt such as sodium metabisulfite to substantially deplete dissolved oxygen in the zone. Thereafter, hydrogen sulfide may be directly added to the zone, being stabilized by the absence of oxygen therein the enhance the mussel kill. Thereafter, as fresh water is added to the zone, the hydrogen sulfide and residual sulfites are oxidized to relatively harmless sulfates.

Abstract: A building heating system includes a plenum for distributing heated air and returning cool air to the heater. In accordance with this invention, additional heat pump means are provided comprising condenser or heat rejecter means positioned in the cold air plenum, heat absorber means which are preferably positioned in the attic of the building underneath the roof and/or in heat exchange relation with warmed gases from a chimney, and conduit and compressor means for providing heat transfer flow communication therebetween.