Some fishing boats include a livewell system. This document describes livewell systems that have multiple modes of operation. The modes of operation include, at least, a first mode with a lower water level and a second mode with a higher water level. While the livewell is operating in the second mode, the tank is nearly full of water. Accordingly, with a nearly full tank, the water in the livewell will resist sloshing around while the boat is navigating rough seas or travelling at high speeds or for long distances. Moreover, the health of the fish in the livewell will be protected because of the water's lessened tendency to slosh around in the livewell.

Some fishing boats include a livewell system. This document describes livewell systems that have multiple modes of operation. The modes of operation include, at least, a first mode with a lower water level and a second mode with a higher water level. While the livewell is operating in the second mode, the tank is nearly full of water. Accordingly, with a nearly full tank, the water in the livewell will resist sloshing around while the boat is navigating rough seas or travelling at high speeds or for long distances. Moreover, the health of the fish in the livewell will be protected because of the water's lessened tendency to slosh around in the livewell.

A drain assembly for a fluid tank having a drain hole therein may include a hollow first member to be coupled with the drain hole, where the hollow first member has at least one opening therein. The drain assembly may further include a hollow second member slidably coupled with the hollow first member and movable along a longitudinal axis of the hollow outer member between first and second positions. The hollow second member may be configured to seal the at least one opening in the hollow first member when in the first position to define an upper spillover level for fluid within the tank, and to unseal the at least one opening in the hollow first member when in the second position to define a lower spillover level for fluid within the tank below the upper spillover level.

A drain assembly for a fluid tank having a drain hole therein may include a hollow first member to be coupled with the drain hole, where the hollow first member has at least one opening therein. The drain assembly may further include a hollow second member slidably coupled with the hollow first member and movable along a longitudinal axis of the hollow outer member between first and second positions. The hollow second member may be configured to seal the at least one opening in the hollow first member when in the first position to define an upper spillover level for fluid within the tank, and to unseal the at least one opening in the hollow first member when in the second position to define a lower spillover level for fluid within the tank below the upper spillover level.

Vessel (52) for farming of marine organisms (60), said vessel (52) comprises several tanks (38) with sea water and the marine organisms (60) that shall be farmed, where said tanks (38) comprises a farming net cage (10) that holds the marine organisms (60) and where the tanks (38) are open to the surrounding sea water (62).

The present invention relates to a movable aquaculture platform suitable for offshore onboard cabin culture and open culture. The aquaculture platform includes a hull with a propulsion system and an onboard control system. A recess recessed downwards based on a plane of a main deck is provided between the front and rear of the hull. Both sides of the recess are formed into an open structure corresponding to double sides of the hull. The recess is provided with a closed cage. The cage and the recess together constitute an open culture cabin. An internal space of the cage is used for culture. The hull is provided with a closed culture cabin below the recess. The present invention can flexibly switch between an onboard closed cabin culture mode, an onboard open cage culture mode and a mixed mode thereof according to different working conditions.

The present invention relates to a movable aquaculture platform suitable for offshore onboard cabin culture and open culture. The aquaculture platform includes a hull with a propulsion system and an onboard control system. A recess recessed downwards based on a plane of a main deck is provided between the front and rear of the hull. Both sides of the recess are formed into an open structure corresponding to double sides of the hull. The recess is provided with a closed cage. The cage and the recess together constitute an open culture cabin. An internal space of the cage is used for culture. The hull is provided with a closed culture cabin below the recess. The present invention can flexibly switch between an onboard closed cabin culture mode, an onboard open cage culture mode and a mixed mode thereof according to different working conditions.

A system is provided that promotes ram ventilation for aquatic animals stored therein. The system includes a horizontally oriented container that maintains fluid flow in one predominant direction with a first end of the horizontally oriented container receiving a first volume of fluid and a second end expelling a second volume of fluid. The second end is provided at an opposite side of the horizontally oriented container than the first end. A slot is provided that extends along a lengthwise direction of the horizontally oriented container between the first and second ends. The slot is positioned along an upper portion of the horizontally oriented container. For example, if the horizontally oriented container is tube-shaped, the slot is provided at an uppermost point on the circumference of a horizontally oriented tube directly across from a point on the tube that contacts an underlying surface such a transom of the fishing vessel.

A system is provided that promotes ram ventilation for aquatic animals stored therein. The system includes a horizontally oriented container that maintains fluid flow in one predominant direction with a first end of the horizontally oriented container receiving a first volume of fluid and a second end expelling a second volume of fluid. The second end is provided at an opposite side of the horizontally oriented container than the first end. A slot is provided that extends along a lengthwise direction of the horizontally oriented container between the first and second ends. The slot is positioned along an upper portion of the horizontally oriented container. For example, if the horizontally oriented container is tube-shaped, the slot is provided at an uppermost point on the circumference of a horizontally oriented tube directly across from a point on the tube that contacts an underlying surface such a transom of the fishing vessel.

A method for processing fish can include transporting fully intact fish to a floating vessel, at least one of weighing and sorting the fully intact fish, forming a layer of frozen slime on an outer surface of skin of the fully intact fish, and freezing the fully intact fish by moving the fully intact fish through an ultra-low air temperature region. Related systems and apparatuses are also provided.