Design, development, and implementation of recirculating aquaria for maintenance and experimentation of deep‐sea corals and associated fauna

Abstract

Here, the development and construction of recirculating aquaria for the long-term maintenance and study of deep-water corals in the laboratory is described. This system may be applied to the maintenance and experimentation on marine organisms in the absence of a natural seawater supply. Since 2009, numerous colonies of Lophelia pertusa as well as several species of associated invertebrates from the Gulf of Mexico have been maintained in the described systems. The behavior of some of these species, including L. pertusa, the corallivorous snail Coralliophila sp., the polychaete Eunice sp., and the galetheoid crab Eumunida picta in the laboratory is described. Additionally, these systems were used for the manipulation of pH and dissolved oxygen for shortterm experiments using L. pertusa. The detailed manipulation of carbonate chemistry in artificial seawater is described for use in ocean acidification experiments.

Response of deep-water corals to oil and chemical dispersant exposure

“…ASW allowed us to accurately maintain desired salinity and temperature for large volumes of water without the potential for introducing contaminants from the ship's seawater system, and to avoid the unreliability of collecting buckets of seawater from over the side in variable sea states. We have used ASW to maintain other coldwater coral species alive in laboratory aquaria for extended periods of time without adverse affects (Lunden et al, 2014).…”

Carbonic anhydrase activity changes in response to increased temperature and pCO2 in Symbiodinium–zoanthid associations

“…In order to manipulate pH in commercial ASW using CO 2 gas, the buffering capacity of the ASW must be reduced. Therefore, prior to experimentation, TA of the ASW was reduced to 2300 μmol kg − 1 using a single injection of 12 M hydrochloric acid (Lunden et al, 2014). Treated ASW was then left to equilibrate in aerated open-air containers for two days, or until pH stabilized at 8.1.…”

Intra-Specific Variation Reveals Potential for Adaptation to Ocean Acidification in a Cold-Water Coral from the Gulf of Mexico

“…In July 2014, the six collections were randomly split between two identical 550 L recirculating units (fully described in Lunden et al, 2014b). Two pH T treatments were selected: 7.90 as the control, and 7.60 as the treatment.…”

“…Because Instant Ocean R at salinity 35 yields seawater with a total alkalinity of ∼3,600 µmol kg −1 , 12.1 N HCl was added to previously prepared artificial seawater (ASW) in order to reduce the total alkalinity to ∼2,300 µmol kg −1 before adjusting the pH (Lunden et al, 2014b). The manipulation of the pH was accomplished by bubbling pure CO 2 gas into the different treatment tanks using an automated CO 2 injection system (American Marine Inc, PINPOINT pH Monitor).…”

“…pertusa were collected in the Gulf of Mexico in April and May 2014 on the R/V Atlantis using the DSV Alvin (Woods Hole Oceanographic Institution). All corals were collected at similar depths, temperature and carbonate chemistry conditions (Table 1) from the Viosca Knoll 826 (VK826) site (Cordes et al, 2008), named for the oil lease block governed by the At the time of arrival, all corals were kept in a 550 L recirculating aquarium system with artificial seawater (ASW) prepared using Instant Ocean R (aquarium sea-salt mixture) and maintained at a temperature of ∼8 • C, salinity 35 ppt, and total alkalinity (TA) ∼2,300 µmol kg −1 (for full description of the system see Lunden et al, 2014b). The corals were fed 20 mL of artificial MarineSnow R (Two Little Fishies) 3 days a week, as per comparable experimental procedures (Lunden et al, 2014a,b;Hennige et al, 2015;Georgian et al, 2016b).…”