Tank Crisis

On Sunday, December 23, 2001 we encountered a extraordinary crisis in the Tansey Tank. The crisis unfolded when we returned from the airport after picking up Nancy from her visit to Texas to help her mom through her hip surgery.

As Nancy called back to Texas to report on her safe arrival, she wandered over to the tank to check on her saltwater friends. After a moment of shock, she yelled out that "the fish are dead." Frank raced over to the tank and yes, fish were lying at the bottom of the tank. The following chronology documents the next 8 hours.

Returned home at 6:10 to find the tank almost deserted of life. There were no normally swimming fish, and the only moving fish was a lemon peel angel struggling to swim in a horizontal position. Several fish littered the bottom of the tank not moving.
Called Rick at 6:12
Raced down to basement to check equipment.
Found temperature to be 55.7 degrees downstairs which was close to ambient temperature 54.6. Inside house temperature was ~70 degrees.
Heater was not on in sump.
Unplugged heater from controller and plugged into AC. The heater immediately came on.
Rick suggested turning off lights and removing fish after guests (10) left.
Rick instructed me to start filtering new water batch, and insert second heater into sump to get temperature up.
Removed first dead fish (sterling angel) and placed in bowl - only one accessible.
Even with two heaters temperature continued to drop to 54.
Returned downstairs and discoved the chiller was full on, that it had been running rather than the heater.
Checked controller settings, which were correct, so there should have been heating rather than chilling.
Unplugged chiller from the controller. Tested the system by replugging the chiller. When the chiller was replugged in, it returned to full on. Disconnected again.
Returned upstairs and started to remove additional fish - lemon peel, orange pakula, second sterling angel, chromis, jawfish, which all appeared to be dead but not to the degree of first sterling angel (color and body rigidity).
Started indirectly heating water to see if fish would respond to gradual re-warming.
Noticed slight movement in some fish swimming on their sides, breathing heavily, barely moving, slight return of color ...
With 6 of our guests, began a concerted effort to rescue the tank.
Started removing every coral, fish, pollop etc possible and started indirect warming process. Caught some of them with the net, but some were so lifeless that they could be picked up by hand.
Fish and inverts began to slowly respond in the warmer water but were still traumatized.
Moved second heater from sump to tank.
Started warming tank water using same indirect method, 4 to 8 cups at a time, repeatedly as soon as water could be raised from tank temperature to low 70's.
9:45 PM – 60 degrees
Raised temperature in .1-.2 degree increments with well over 100 trips from kitchen up ladder to tank.
Maintained bucket temperatures as necessary.
Several hours later, as the water began to gradually warm, other fish, and sea horse were captured as they became visible - added to warming bucket. A few fish could not be captured and some corals could not be removed.
Fish continued to improve but still traumatized.
12:00 am - 65.3 degrees
Added air stone to holding bucket around midnight.
1:00 am - 67.6 degrees
2:00 am - 69.3 degrees
Continued warming tank until 2:30 am when tank reached 70 degrees.
Added corals and raised water temperature to 71.
Returned fish, which continued to labor but much improved from time of removal and so I went to bed feeling that all that was possible had been done.
Continued monitoring temperature as it continued to rise slowly.
Multiple fish continued in distress early in the morning, but their condition was improved over what it had been when they were returned to the tank.
Tank at 75 degrees by 7:00 am
Tank reaches 76 degrees at 9:45 am
Disconnected second heater.
Other fish which weren't captured appeared slowly.
Lost/damaged corals/plants: ganopura, carnation coral, fuzzy star coral, toadstool coral, brown star pollop coral, small soft coral, carpet anonmae, radinthus anonmae, yellow fox coral, elegance coral, marble colarpa, grape colarpa, dinner plate colarpa, red kelp, cats eye pollops (2 colonies) ...
Lost fish: 4 sterling angels, sea horse, 3 chromi, 2 mandarin goby, blue tang, 2 file fish
Some fish and corals remain distressed, and there is damage to live rock and algaes
Even with the significant losses, we saved far more than we lost and the effort prevented a complete loss of the tank live stock.