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Sounds Fishy?

FOSS Newsletter Staff
September 08, 1998 | Live Organisms

The following question was forwarded to the FOSS staff at the Lawrence Hall of Science by Susan Hardy, a FOSS Regional Sales Manager.

Has the specter of death reared its ugly head regarding any of your living materials when they get to the classroom? I am specifically asking about guppies. Lately, we have been shipping fresh, healthy guppies to our schools from a reputable local vendor. Within a day or two, they are dead, while the remaining fish back at the store are still happily swimming about.

Our prime suspect right now is contamination of the aquarium tanks, which we ship out in the modules. It's possible the residue from a cleaning agent remained on the tank walls and spelled imminent doom for any fish placed in them.

Sound familiar? Plausible? I'd like to hear from anyone who has dealt with this or has ideas.


Greg Calvetti, Manager
ASSET Materials Support Center

Larry Malone responds:

Guppy problems are not new; I've been around them for three decades. From their reputation you'd think they would be bullet proof, indestructible little critters. But, quite to the contrary, they are sensitive to changes. Once established, they are forever, but I don't know what your specific problem might be, so let me suggest several variables to consider.

Your suggestion of contaminant residue in the containers sent out to the schools is possible, but I would guess that routine attention to rinsing during the cleaning process would make this a very low probability variable. Guppies are on the edge of tropical. They are sensitive to temperature change, particularly cooling. A chilling of several degrees over a short period of time may be enough to cause a mortal shock.

Water purification (chlorination) can be deadly. What chemical is used in the Pittsburgh area? Traditional chlorination is relatively easy to manage. Open exposure (aging) for a day, or boiling and cooling eliminates chlorine. If, however, you have chloramines in your water, chemical treatment is required. Chloramines do NOT dissipate with time and must be neutralized chemically. If local water is a problem, I recommend bottled spring water, at least for starters at the time of delivery.

Oxygen requirements go up during times of stress, like relocation. It is desirable to keep the time in transit to a minimum, and it might be a good idea to have an air bubbler in the new container for a period of time to insure good oxygen saturation right after relocation.

Relocation shock is a catch-all category for mortality due to no identifiable cause. Sometimes it seems like all due attention has been paid, but the fish still fail. We need a fish psychologist to look into the subject, interview a few of the survivors, and generate a profile of the Relocation Stress Syndrome. Maybe a little Prozac in the water just before shipment...

I'd recommend that teachers anticipate the arrival of the fish by having aquaria filled with treated water sitting around for at least three or four days before arrival. Then use the standard precaution for reducing temperature shock—float the shipping container, fish and all, in the new aquarium to equilibrate the temperature over a period of an hour or so. Then dump them into the new abode and watch them do their fishy thing.

If you haven't already, set up some containers, hike off to your vendor, purchase five batches of guppies, and experiment. Have some treated, four-day-old water ready in several containers, straight tap in another, and bottled water in one. Let one batch get cold during shipment, and do an immediate transfer of one batch when you get them to your "lab." Use a bubbler in one. You get the idea. Have some fun with it, and let me know if anything seems to work. We'll put it in the FOSS Newsletter.

You might try contacting some local experts if all else fails. You have the NY-PENN Council of Aquarium Clubs in your neighborhood. Here's their website: