| 摘要 |
PURPOSE:To rapidly disperse a concentrated solution of fertilizer into a nutritive solution and to always control concentration in high accuracy by feeding a concentrated solution of fertilizer to a reflux pipe into which the nutritive solution is returned from a culture tank. CONSTITUTION:In a water culture device wherein a nutritive solution in a nutritive solution tank 1 is raised to a culture tank 3 by a pump 2, necessary water, oxygen and nutritive substance are fed to cultured plants and then the nutritive solution is returned through a reflux pipe 4 to the nutritive solution tank 1, a feed pipe of concentrated solution of fertilizer is connected to the reflux pipe 4 and the concentrated solution of fertilizer is supplied from a fertilizer tank 6 through the feed pipe 7 to the reflux pipe by output of a sensor 5 to detect electrical conductivity of the nutritive solution. |
