A First Aquarium Was a Great Teacher—and We're Still Learning mistakes are bound to happen you should learn from it and move on.

A First Aquarium Was a Great Teacher—and We're Still Learning mistakes are bound to happen you should learn from it.

Not too far from where I grew up, there was a dank and dingy tropical fish store where my sister bought a 26-gallon tank. She had saved up allowance money for the better part of a year so that she could get the deluxe kit.

I'll never forget the exuberance of the moment when she brought it home, dragged a garden hose through her bedroom window and began filling it up, plopping in first the under-gravel filter, then the gravel, and finally the decorations (which were nothing more than some rocks we'd gathered from the back yard).

The following day, we pooled our life savings and headed for the fish store. Armed with just $6 and the first volume of the Baensch Atlas of freshwater fish, we felt confident enough to bring our first few fish home.

We had no clue that we had just infected the entire system.

Dumpster diving
Hours later, we emerged from the darkness of the store, squinty-eyed, with bags of fish in our hands. We had exchanged every penny we owned for six neon tetras and an albino Corydoras catfish. It was on the way home that we decided to take a shortcut through the alley of the shopping center to take a gander at the contents of the fish store's Dumpster—maybe there were some useful aquarium supplies that had been thrown away?

Among the empty fish bags and outdated chemicals, we were shocked to discover that there were bags of both coolie loaches and marble hatchets ... alive, but not well. The water they were in was a bluish green color from the medication used to treat them. Apparently, the expense of the medication had surpassed the actual wholesale value of the fish.

Rescuing the sick
We took turns at rummaging and standing lookout. In all, we rescued several ghost glass fish, some guppies, a huge bag of coolie loaches, and a few marble hatchets. We pedaled home with so many fish in our arms that we could barely use our handlebars to steer.

When we got home, we dumped the fish into the aquarium—the sick, and the well, together. We sat, mesmerized by our new fish, and I remember thinking how cute it was that some of them would scratch themselves against the rocks. We had no clue that we had just infected the entire system.

Infecting the healthy
The next morning we awoke to an aquarium in which the dead outnumbered the living. Most of the loaches and guppies had died, as well as a few of the neon tetras. What fish were left alive had been infected: Their bodies and fins looked as though they had been rolled up in miniature bubble wrap. After consulting our fish book, we discovered that we had committed multiple mistakes—not using a quarantine tank for sick fish and newcomers being first among them.

So off we went again to the fish store to get medication and rock salt (we learned from our book that this would nearly double the effectiveness of the medication). We successfully treated the fish, losing only a few more of the loaches. It was the start of our fish education, but not the last of our mistakes.

Learning experiences
Now that all signs of disease were gone, it was time to perform a water change. We wanted to be really thorough with the cleaning, so we placed all the remaining fish in a bucket. Then, using a gravel vacuum, we drained every last drop of water from the aquarium (goodbye helpful bacteria!).

To be on the safe side, we thought it best that we disinfect the gravel with some of Mum's detergent (never realizing that soap kills fish). How we averted tragedy on this one, I'll never know—but I suspect that the hour we spent rinsing the gravel had something to do with it.

Compatibility, what's that?
Our next great discovery was that the irrigation ditch close to our home was seething with mosquito fish, frogs, turtles, and aquatic plants, all of which eventually did hard time in that little 26-gallon tank.

Knowing little about fish compatibility, we dumped them in—the more, the merrier. The mosquito fish were just awful—they bullied and nipped the other, more peaceful fish. They had ravenous appetites, too, often eating all the bugs and baby snails we could find in our garden, as well as the flake food we attempted to feed the other fish.

Trial and error
Even equipped with an atlas, it was largely by a process of trial and error that my sister and I blundered through the ABCs of aquarium keeping. Collectively, she and I killed more fish than either of us are willing to admit. We were the Dr. Kevorkians of the fish realm. We've both come a long way in our knowledge and understanding of the hobby. I have several aquariums of my own and make my living taking care of other people's fish. I recently visited Karen in San Diego, where she still keeps that same 26-gallon aquarium (now with a custom oak stand and canopy). I asked her how it was working out. "I still kill fish once in a while," she said. "I haven't learned everything yet; I guess it takes a lifetime.