Abstract: A method and a system are described for trade of goods, in particular electricity, water, fuel gas, and the like, and the method is characterised in that a computer, which is connected to a measuring unit for consumption of electricity, water, gas and the like, is arranged by means of a link to be connected to a trading system for the mentioned electricity, water, fuel gas and the like with the computer arranged to be programmed for conditions for the trade. The method and system are applied to tie the unit price for the goods at invoicing, directly to the actual price for the time interval when the goods consumption really occurred, or to carry out changes of the conditions for the goods delivery and the like.

Abstract: An apparatus for breeding fish comprises a pool having an impervious annular outer wall for floating in a body of water. A water distributor is located in an upper portion of the pool for directing the flow of water into the pool to set the volume of water in the pool into a rotating motion. An exhaust is located in the bottom of the pool for the free flow of water and debris from the pool into the surrounding body of water. The water distributor includes a regulating handle for changing the direction of flow of the water from the distributor to regulate the speed of the rotating volume of water in the pool.