Interviews with Aquarists

 

Facility #1: major US Public Aquarium

  • Marine Water Source: Natural Seawater
  • Lithium Content: 300 parts per billion
  • Aquarium Capacity: 3,000 gallons
  • Filtration: Algal scrubber

Water Chemistry: Nutrients very low, alkalinity close to natural seawater levels. pH less than 8.0 as is, over 8.0 with regular caustic addition. Elevated iron levels.

Salient Remarks: Reef display containing a diversity of fishes, corals, and other invertebrates. Most lifeforms do quite well with low mortality. Cannot maintain certain organisms of prey probably due to predation. Few isolated incidences of coral disease, but most do very well and continue to thrive. Significant reproductive activity including asexual budding, planktonic larvae, and many egg cases. However, most free floating and swimming offspring cannot survive the filtration and/or predators within the system. No deformities observed.

 


Facility #2: major US Public Zoo and Aquarium

  • Marine Water Source: Synthetic Sea Salt prepared "in-house" using various purified salts
  • Lithium Content: 3,100 parts per billion
  • Aquarium Capacity: 36,000 gallons
  • Filtration: Sand filters and ozonation

Water Chemistry: Basic parameters including nutrients, pH, and alkalinity are measured routinely and remain at quite normal levels.

Salient Remarks: Primarily fish display consisting of sharks, rays, and Teleosts with no invertebrates. Moderate success with most organisms. Some shark breeding observed producing egg cases which did not hatch.

 


Facility #3: major US Public Aquarium

  • Marine Water Source: Instant Ocean commercial salt mix
  • Lithium Content: 220 parts per billion
  • Aquarium Capacity: Large system - 475,000 gallons, reef system - 400 gallons
  • Filtration: Large system uses sand filters with ozone and reef system uses large protein skimmers

Water Chemistry: Large system has typically elevated nitrates with low pH. Carbonate/borate buffers are used with moderate success to increase pH levels. Reef system has acceptable pH levels without buffer addition. A variety of trace elements and caustic are used regularly.

Salient Remarks: Large system supports a variety of shark and fish life with good success. Average disease occurrence and mortality reported. Although no breeding program exists, many eggs have been observed in the system. Unfortunately, none survive probably due to predation. The reef system supports some fish and a variety of corals and other invertebrates with moderate to above average success. Many of the soft corals proliferate. Shrimp eggs have been observed.

 


Facility #4: major US Public Zoo and Aquarium

  • Marine Water Source: Synthetic Sea Salt prepared "in-house" using various purified salts
  • Lithium Content: 5,600 parts per billion
  • Aquarium Capacity: 100 gallons
  • Filtration: Gravel bed type

Water Chemistry: Nutrients fairly low and pH maintained with carbonate salts.

Salient Remarks: Invertebrate display consisting primarily of mollusks including gastropods, clams, octopus, and squid. Many specimens are difficult to maintain in captivity for prolonged periods. Several instances of reproduction among different mollusks produced eggs which never developed. One octopus which was impregnated before capturing, laid many eggs and successfully protected them until hatching. All of the young died within two weeks, although it was attributed to nutritional reasons. The mother octopus also died shortly thereafter which is common among these cephalopods.

 


Facility #5: major US Public Zoo and Aquarium

  • Marine Water Source: Instant Ocean commercial salt mix
  • Lithium Content: 260 parts per billion
  • Aquarium Capacity: Several systems ranging from 82,000 to 218,000 gallons
  • Filtration: Biological and ozonation

Water Chemistry: No major problems although systems are relatively new and not stabilized yet.

Salient Remarks: Lifeforms consisting of mostly sharks and Teleosts. Good success to date with one exception where many fish died due to accidental volatile chemical contamination. No active breeding program.

 


Facility #6: Amateur aquarist

  • Marine Water Source: Coralife commercial salt mix
  • Lithium Content: 5,600 parts per billion
  • Aquarium Capacity: 150 gallons
  • Filtration: Wet/dry biological with protein skimming

Water Chemistry: Nutrients low, regular addition of carbonate/borate buffer to maintain pH above 8.1 and high alkalinity. Frequent addition of trace elements.

Salient Remarks: Moderate success with a wide range of reef organisms. Typical reef fish do quite well in this system, but invertebrate success has been extremely varied. A few hard corals exhibited moderate proliferation, but many did not thrive and ultimately perished. In particular, a number of clams purge and die within days after introduction to the system. Ironically, other clams which have been living in the system for extended periods, seem to survive adequately. No evidence of reproduction among any of the lifeforms has been observed.

 


Facility #7: major US Public Aquarium

  • Marine Water Source: Synthetic Sea Salt prepared "in-house" using various purified salts
  • Lithium Content: 4,900 parts per billion
  • Aquarium Capacity: 90,000 gallons
  • Filtration: Sand filters and ozonation

Water Chemistry: Elevated nitrates and regular carbonate/bicarbonate addition for buffering.

Salient Remarks: Average success with a variety fishes and some seahorses. Average mortality and typical diseases were reported. Lack of success with invertebrates forced aquarists to utilize smaller systems with different salt mixes for these more challenging lifeforms. Successful breeding of sharks was reported and some Ocean Perch fry were hatched. Unfortunately, the perch fry had abdominal cavities which did not close. They all died within days after hatching, depending upon the severity of the abdominal cavity opening.

 

 

 

ACKNOWLEDGMENTS

Special thanks to the following individuals and institutions for their valued input which made this work possible:

Bill Hoffman, Smithsonian Institution, Washington, DC

Andy Keech, National Zoological Park, Washington, DC

Jeff Krenner and Sallie Nicholas, UnderWater World at Mall of America, Bloomington, MN

Kris Petrini, Minnesota Zoological Garden, Apple Valley, MN

Kent Semmen, John G. Shedd Aquarium, Chicago, IL (now at Brookfield Zoo, Brookfield, IL)

Kathy Vires, Omaha's Henry Doorly Zoo, Omaha, NE


 

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