Mesocosm Facility

The Bermuda Marine Mesocosm Facility (BMMF) is a robust and versatile state-of-the-art outdoor facility for experimental work and organism culturing.

The originally purpose-built mesocosm facility supported by the Heising-Simons Foundation was first used in 2018 and underwent a major upgrade with an NSF facility grant (#2129274) in 2022/2023. The BMMF provides scientists with an opportunity to conduct research in controlled aquatic environments under near-natural conditions, meaning natural sun light and seawater that is pumped from the close-by Reach. There are several experimental basins and aquaria that can be run simultaneously and are designed with the potential to manipulate a range of environmental factors, such as temperature, light, CO2 concentrations, flow rate, and nutrients. Originally constructed for thermal stress experiments, the mesocosm facility provides for a replicated and robust experimental design that is ideal for research on a variety of topics, such as eco-physiology, reproduction and spawning, biological recovery and ecosystem resilience.

The mesocosm facility has the following key components:

Component                         Amount and characteristics


  • 12 x 500-L basins
  • 4 x 1500-L basins – elongated, can be converted into flumes
  • Adjustable height of bottom grates

Light intensity control

  • Roof: Scaffolding holding a waterproof & light permeable (~75%) greenhouse foil
  • Lids for each basin with exchangeable shading material (e.g., mosquito netting) for further light reduction

Temperature control

  • 12 x AquaLogic DSHP-9 Heat Pumps, one for each 500-L basin
  • 4 x AquaLogic HS-2 Heat Pumps, one for each 1500-L basin
  • These high-capacity Heat Pumps can chill and heat and are controlled by a temperature controller with a thermometer inside each basin.
  • Plywood lids for each basin (complete darkness)

CO2 supply and pH monitoring

  • 4 levels of CO2 (ambient + 3 levels of CO2-enrichment); CO2 supply regulated by mass-flow controllers and directly bubbled into 3 x 200-L flow-through header tanks; flow to individual basins is adjustable
  • Simultaneous and constant CO2 supply to up to 9 basins.
  • Automated pH measurements in all basins via a centralized pH sensor (DURAFET III , Honeywell Process solution) and remote-controlled pumps. Control and logging software: LabView

Water supply and flow

  • Continues supply of seawater from adjacent Reach
  • Sediment filter
  • 2 x 5,500-L header tanks for seawater storage
  • Total capacity of seawater supply: 9,000 L/h
  • Flow meters and gate values at each inflow to the basin
  • Fresh water hose

Aquarium setup

  • Up to 30 x 60-L aquaria available that can be placed inside basins


  • 2 - 4 power outlets (110V) above each basin

Laboratory container

  • 20-foot shipping container converted into a lab space with cabinets, bench space, various power outlets (110V) and a freshwater sink
  • For (semi-)dry work in an air-conditioned space

Utility golf cart

  • For quick and easy transport of life organisms from the boat to the BMMF and for transport of equipment.


Note: This webpage will gain further updates over the next few months with more detailed information about the capabilities of the upgraded BMMF.

Facility Contact

Dr. Yvonne Sawall

Assistant Scientist/Assistant Professor, School of Ocean Futures

Tel: 441-297-1880 x137


Dr. Samantha de Putron
Associate Scientist/Assistant Director of University Programs/Senior Lecturer
Tel: 441-297-1880 x250


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