A system for growing algae includes a photobioreactor comprising a tubular structure having inner and outer surfaces, an annular space defined between the inner and outer surfaces, an inlet to allow an algae slurry to enter the annular space, and a mechanism configured to produce radially-directed contractions and expansions in the tubular structure. At least one of the inner and outer surfaces is transparent to at least some wavelengths of light useful for growing algae within the algae slurry.

Methods and systems, including computer programs encoded on computer-storage media, for controlling a system for growing seaweed are described. Some implementations of a method include forming a substrate loop inoculated with seaweed spores; arranging the substrate loop about a pulley; submerging the substrate loop to grow the seaweed; determining, using a seaweed farm controller, that the seaweed has grown to a pre-determined size; and based on the determination that the seaweed has grown to a pre-determined size: providing instructions to the pulley to feed a section of the substrate loop to a harvesting unit; providing instructions to the harvesting unit to separate the seaweed attached to the section of the substrate loop; providing instructions to a cleaning unit to clean the section of the substrate loop that is freed from seaweed; and providing instructions to a seeding unit to inoculate the cleaned section of substrate loop with seaweed spores.

Methods and systems, including computer programs encoded on computer-storage media, for controlling a system for growing seaweed are described. Some implementations of a method include forming a substrate loop inoculated with seaweed spores; arranging the substrate loop about a pulley; submerging the substrate loop to grow the seaweed; determining, using a seaweed farm controller, that the seaweed has grown to a pre-determined size; and based on the determination that the seaweed has grown to a pre-determined size: providing instructions to the pulley to feed a section of the substrate loop to a harvesting unit; providing instructions to the harvesting unit to separate the seaweed attached to the section of the substrate loop; providing instructions to a cleaning unit to clean the section of the substrate loop that is freed from seaweed; and providing instructions to a seeding unit to inoculate the cleaned section of substrate loop with seaweed spores.

An algae scrubber system operates via a flow of water and a power source. The algae scrubber system does not require a bubbler. The rate of flow of the water may be variable. The algae scrubber system includes a screen that is configured to be removed from the system without shutting off the flow of water through the system and without spilling the water. The system includes a main body with a water distributor providing water to a tray. A screen hangs from the tray to and grow light(s) encourage algae growth on the screen.

An algae scrubber system operates via a flow of water and a power source. The algae scrubber system does not require a bubbler. The rate of flow of the water may be variable. The algae scrubber system includes a screen that is configured to be removed from the system without shutting off the flow of water through the system and without spilling the water. The system includes a main body with a water distributor providing water to a tray. A screen hangs from the tray to and grow light(s) encourage algae growth on the screen.

A method of growing algae in a cultivation container is disclosed. In some the method may include: circulating, via the cultivation container, in a closed loop, a first predetermined amount of gas mixture comprising a first type of gas and at least one second type of gas, the gas mixture may enter the container via one or more entrance spargers and exit via at least one exit pipe, the first type of gas may contain CO.sub.2 at a known first amount; receiving signal indicative of the amount of CO.sub.2 or H.sub.2S, in the gas mixture; when the signal indicates that the amount of CO.sub.2 drops below a first predetermined level or when the signal indicates that the amount of H.sub.2S rises above a first predetermined level, extracting a second predetermined amount of the gas mixture from the cultivation container: and adding an amount of the first type of gas to the gas mixture, equal to the second predetermined amount.

A method of growing algae in a cultivation container is disclosed. In some the method may include: circulating, via the cultivation container, in a closed loop, a first predetermined amount of gas mixture comprising a first type of gas and at least one second type of gas, the gas mixture may enter the container via one or more entrance spargers and exit via at least one exit pipe, the first type of gas may contain CO.sub.2 at a known first amount; receiving signal indicative of the amount of CO.sub.2 or H.sub.2S, in the gas mixture; when the signal indicates that the amount of CO.sub.2 drops below a first predetermined level or when the signal indicates that the amount of H.sub.2S rises above a first predetermined level, extracting a second predetermined amount of the gas mixture from the cultivation container: and adding an amount of the first type of gas to the gas mixture, equal to the second predetermined amount.

Provided are a culture apparatus and a culture method with which microalgae can be cultured satisfactorily. The culture apparatus includes a plurality of culture tanks and a water storage tank, and cultures microalgae in a culture solution. Each of the plurality of culture tanks has a translucent accommodating portion containing the culture solution and microalgae. The volumes of the accommodating portions of the plurality of culture tanks are different from each other. The water storage tank has a translucent water storage unit for storing a stored water. The plurality of culture tanks are selectively arranged in the water storage unit.

Provided are a culture apparatus and a culture method with which microalgae can be cultured satisfactorily. The culture apparatus includes a plurality of culture tanks and a water storage tank, and cultures microalgae in a culture solution. Each of the plurality of culture tanks has a translucent accommodating portion containing the culture solution and microalgae. The volumes of the accommodating portions of the plurality of culture tanks are different from each other. The water storage tank has a translucent water storage unit for storing a stored water. The plurality of culture tanks are selectively arranged in the water storage unit.

A system, comprising a Trickle Bed Reactor (TBR), a microalgae cultivation module, and a feedback module is used to sustainably boost CO2 fixation for growing micro-algae. The TBR comprises a packing material in the form of non-porous particles with a high surface-to-volume ratio, forming a substrate for attachment of Volatile Fatty Acid (VFA) producing microbes, fed with CO2 (and/or CO), H2, nutrients, and a moistening liquid. The TBR output is fed to the microalgae cultivation module which uses micro-algae selected or adapted for increased productivity in the presence of VFAs. No CO2 needs to be fed to the microalgae cultivation module. At least part of the output of the microalgae cultivation module is fed by the feedback module back to the TBR either as a source of nutrients or for as a means backflushing for unclogging or expulsing the packing material from the TBR for cleaning/disinfection. The overall CO2 balance of the system operation is negative.