Provided is a multi-tube nozzle for use in eradicating harmful aquatic organisms, which physically kills harmful aquatic organisms while feeding water and thus allows intake water to be fed directly into a culture tank or a ballast tank without the need for a pretreatment tank, chemicals, neutralizers, etc. A multi-tube nozzle (A) for use in eradicating harmful aquatic organisms includes at least three nozzle tubes (1) that are provided adjacent to each other. The nozzle tubes (1) each includes: an inlet-side opening section (2) having an inner diameter that decreases from an inlet opening toward a throat section (3) located in the middle of the tube; an outlet-side opening section (4) having an inner diameter that increases from the throat section (3) toward an outlet opening; and the throat section (3) having a smallest inner diameter. The adjacent nozzle tubes (1) are spaced apart by a distance such that the adjacent inlet-side opening sections (2) overlap each other. A wall (5) of an overlapping portion (6) of the inlet-side opening sections (2) is cut in a U shape. An uncut portion (5a) between the adjacent U-shaped cut portions (5b) forms a sword-like pointed tip.

The present embodiments relate to selectively growing microalgae of a size suitable for the culturing of planktivorous finfish such as sardines, menhaden, herring, anchovy or shellfish such as oysters, clams, mussels, scallops, and sessile invertebrates such as sponges, coral, sea jellies, and other Cnidaria, or sedentary polychaete or bristle worms. A nitrogen to phosphorous content ratio of a nutrient medium may be measured. Nitrogen and/or phosphorous may be added to adjust the nitrogen to phosphorous content ratio in the nutrient medium to a ratio of 100:1 or higher. Microalgae may be grown in the adjusted nutrient medium. The environment may be controlled to produce microalgae with a predetermined diameter.

The present embodiments relate to selectively growing microalgae of a size suitable for the culturing of planktivorous finfish such as sardines, menhaden, herring, anchovy or shellfish such as oysters, clams, mussels, scallops, and sessile invertebrates such as sponges, coral, sea jellies, and other Cnidaria, or sedentary polychaete or bristle worms. A nitrogen to phosphorous content ratio of a nutrient medium may be measured. Nitrogen and/or phosphorous may be added to adjust the nitrogen to phosphorous content ratio in the nutrient medium to a ratio of 100:1 or higher. Microalgae may be grown in the adjusted nutrient medium. The environment may be controlled to produce microalgae with a predetermined diameter.

Embodiments for managing aquaculture production by one or more processors are described. Information associated with an aquaculture site is received. The information includes at least a current stocking density of the aquaculture site. A recommended time for harvesting is determined based on the received information. A signal representative of the recommended time for harvesting is generated.

Embodiments for managing aquaculture production by one or more processors are described. Information associated with an aquaculture site is received. The information includes at least a current stocking density of the aquaculture site. A recommended time for harvesting is determined based on the received information. A signal representative of the recommended time for harvesting is generated.

A shellfish trap system and a method for developing a reef are provided. The shellfish trap system includes a growing assembly, a first protective layer, and a second protective layer. The growing assembly includes a material which is conducive for shellfish in the pediveliger larvae stage to attach to. The first protective layer substantially envelops at least a first portion of the growing assembly during a first developmental stage of the shellfish and is removed from the growing assembly after completion of the first developmental stage. The second protective layer substantially envelops at least a second portion of the growing assembly during a second developmental stage of the shellfish, wherein the at least a second portion of the growing assembly is submerged in water during the second developmental stage of the shellfish.

A shellfish trap system and a method for developing a reef are provided. The shellfish trap system includes a growing assembly, a first protective layer, and a second protective layer. The growing assembly includes a material which is conducive for shellfish in the pediveliger larvae stage to attach to. The first protective layer substantially envelops at least a first portion of the growing assembly during a first developmental stage of the shellfish and is removed from the growing assembly after completion of the first developmental stage. The second protective layer substantially envelops at least a second portion of the growing assembly during a second developmental stage of the shellfish, wherein the at least a second portion of the growing assembly is submerged in water during the second developmental stage of the shellfish.

Apparatus, systems and methods that include a fastener that allows for a float to be easily detached from and securely reattached to an aquaculture cage. For example, a method provides multiple toolless approaches to submerse an aquaculture cage that is buoyant in water when attached with a fastener to a hollow float defining a volume filled with air. The method includes in a first approach, detaching the hollow float from the aquaculture cage by releasing the fastener without using a tool to allow the cage to sink in the water and in a second approach, with the hollow float attached to the aquaculture cage, at least partially filling the float with fluid to fully submerse both the cage and the hollow float beneath a surface of the water.

Apparatus, systems and methods that include a fastener that allows for a float to be easily detached from and securely reattached to an aquaculture cage. For example, a method provides multiple toolless approaches to submerse an aquaculture cage that is buoyant in water when attached with a fastener to a hollow float defining a volume filled with air. The method includes in a first approach, detaching the hollow float from the aquaculture cage by releasing the fastener without using a tool to allow the cage to sink in the water and in a second approach, with the hollow float attached to the aquaculture cage, at least partially filling the float with fluid to fully submerse both the cage and the hollow float beneath a surface of the water.

Disclosed herein is a feed composition that promotes the growth of zooplankton, enhances the survival rate of zooplankton, is safe, and has little adverse effect on the environment. The feed composition for zooplankton contains PHA.