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Stress: Enemy Number One

You're at the aquarium store, and have decided on some new fish for your freshwater tank. You ask the shopkeeper to catch you the new jewel you have in mind for your collection-- that one, no-- in the back, that one right there. And the shopkeeper obediently chases your pick in and out, around and through all the decorations and other identical fish in the tank-- never mind that two others already accidently swam into the net on their own. Thus begins only the first of many stressful events the fish you have chosen will endure today before it gets to your home aquarium-- to say nothing of a few more after it arrives there.

Now, having caught your prize, the shopkeeper plunks it into the container of dechlorinated water dipped from the 5-gallon bucket at the fish bagging station-- no sense having to refill tanks after dipping water from them all day, now, is there? And then it's sploosh! into the bag, and a blast of air from the "oxygen" tank, and then spin, spin, spin, and the sloshing around as the rubber band is wound around, around, around. Wait! Before you put it in the paper bag, let me hold it up to the light and look at it one last time before you ring it up.

Now it's time to go home. But, half way there:

It's such a hot day-- let's stop at Baskin Robbins for a cool treat. A banana split would be great-- but, hmmm... Don't want to risk messing up the upholstery, we'll have to eat it here-- should only be 20 minutes, or so.

OK, that was great, but time to get on home. Sure gets hot fast in this car on a day like today. If we ate ice cream in the car, it surely would have melted all over the place.

Finally home-- just float the fish in the tank while I change the oil in the wife's car. It shouldn't take me too long.

Wow, who'd have thought it would take an hour and a half to get that darned oil filter changed. Well, I guess that's been plenty of time-- go ahead and dump the new fish out into the tank.

Hmm, it's hiding in the back-- get that algae cleaner stick and chase it out front so we can see it. Go ahead and turn on all the lights, too, so we can get a real good look at it.

And the next day:

Darn, only a day later and the new fish is dead. Have to go to the aquarium store and get my money back. They must have sold me a sick fish...

What went wrong? If your answer is "pretty much everything", you're correct. The fish wasn't sick at all-- it was just stressed to death.

So let's see the list of what stresses the recently deceased endured before its untimely demise:

  • First, there was all that chasing around the store tank, increasing heart and respiration rate,
  • only to be unceremoniously plunked into a bag of water not of the same temperature or pH as the tank,
  • being spun around like a washing machine,
  • and held up to a bright light inches away.
  • Then left in a hot car, rapidly changing water temperature a second time,
  • followed by an overly lengthy soak in the home tank, with oxygen levels in the small amount of bag water depleting to almost nothing, and CO2 and ammonia levels increasing by the minute.
  • Then being dumped into the tank, whose pH surely differed from that of the water in the bag,
  • followed by another round of chasing and prodding and bright lights...

In a large body of water-- a pond, lake or stream-- changes take place very slowly. Temperature may vary by only a couple of degrees over the span of several months. The pH of the water is nearly constant. A single dead fish makes no impact on the water quality whatsoever.

But, in the aquarium, changes can occur rapidly enough to cause great stress on the animals within, and stress leads to disease, and, likely, to death.

In a perfect world, every effort should have been made to minimize stress. We didn't even consider the stress that the same fish likely went through only days before in its transit from supplier to shopkeeper-- it was likely far worse. So what should we do in the future?

  • Ask the shopkeeper how long the fish you want has been at the store. If it's been 5-7 days, and the fish has no sign of disease, the first test has been passed.
  • Request that decorations be temporarily removed from the tank before catching the fish, and that multiple nets be used, if possible, to minimize the catching time.
  • Demand that water from the same aquarium be used to bag the fish, and that it be gently poured from container to bag.
  • Turn off the aquarium lights and float the bag for 20-30 minutes maximum.
  • Open the bag and add water from the aquarium equal to half the water in the bag.
  • Roll down the top of the bag to form a cuff so the bag does not collapse or sink. Clip it to the tank frame if necessary.
  • 15 minutes later, add another similar amount of tank water to the bag.
  • In another 15 minutes, transfer your new fish into the tank using a small net that will fit into the bag-- don't pour the bag water into the tank.
  • Leave the lights off until tomorrow.

Using the same tank water for transport, minimizing the time from store to home, equalizing temperature and water chemistry before release, avoiding the introduction of potential pathogens from the aquarium shop's tankwater, and allowing the new inhabitant time to comfortably settle in the temporarily darkened tank-- all contribute to giving your new fish the best chance to survive and thrive.

1 thought on “Stress: Enemy Number One

  1. Gerwin

    AWESOME, you had to have worked retail before

    it never ceases to amaze me the number of hobbyists who ask how long they can stay in the bag, as if they drove from 2 states away , only to find out they want to catch a bite or go grocery shopping before getting home with their 50.00 rare fish, they special ordered a month ago. geeeeze

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