Self-closing aquarium valves to consistently acclimate fish to temperature and pH of a new tank with minimal monitoring are described. The self-closing aquarium valve includes a frame, an automatic stopper hingedly connected to the frame that closes automatically, and a hose that provides fluid communication from the new tank to a holding tank, and an adjustable flow control. The self-closing aquarium valve provides consistent acclimation of a fish from the holding tank to a new tank through the adjustable flow control with minimal monitoring with the automatic stopper.

Self-closing aquarium valves to consistently acclimate fish to temperature and pH of a new tank with minimal monitoring are described. The self-closing aquarium valve includes a frame, an automatic stopper hingedly connected to the frame that closes automatically, and a hose that provides fluid communication from the new tank to a holding tank, and an adjustable flow control. The self-closing aquarium valve provides consistent acclimation of a fish from the holding tank to a new tank through the adjustable flow control with minimal monitoring with the automatic stopper.