Thursday, April 2, 2015

Aquaponics Update: Strawberries and a fish emergency

First, the good news. We grew strawberries in our indoor aquaponics system! Three strawberries, to be precise. In deep February, with over 70" of snowfall this month, words cannot describe how incredible it feels to bite into a perfectly ripe strawberry. To grow them, I transplanted a strawberry plant from last summer's outdoor planter, and hand pollinated the flowers.

The rest of our grow bed has been transformed into a kitchen herb garden for the winter months. We're growing scallions (I just planted the roots from a bunch I bought at the grocery store), dill, cilantro, and garlic greens. All of these are great for a little sprig of fresh green garnish for our hearty winter meals.

Now for the bad news.

Our miniature aquaponics system has been chugging along since last summer with no problems. A few weeks ago, we moved it into the kitchen so that we would have more access to the plants and so we could keep a closer eye on the fish.

A few weeks after that, the fish seemed sluggish. I looked closer, and to my horror I found scary looking red spots around its gills, vent, on its tail--everywhere. Having killed (accidentally!) many goldfish as a child, I felt this must be a signal of the fish's impending demise.

Now, this fish is a survivor. We call it our "rescue fish". It came to live with us after its pond was filled in. I found it flopping around in the muck after I finished bailing all the water. I figured it was a long shot, but I ran home and got a pitcher of water to transfer the fish to. Despite being thrown into different temperature and pH chlorinated water, the fish pulled through. Later, when its tank shattered in my hands during a move, the fish survived the resulting counter-flopping (I ended up with a nice slice in my hand). Could it be that our rescue fish's luck had finally run out?

I did what any DIYer would do--I searched the fish's symptoms online. It didn't look good; the Internet recommended broad spectrum antibiotics, or maybe even injections. Who knew you could give shots to a fish? Like dummies, we called our local fish store to see if they had antibiotics. The wise, stern voice on the other end of the line said, "You don't need antibiotics. You can probably cure it with a salt bath. Bring a water sample on by."

At the fish store we learned that our water had high levels of nitrites, and the fish expert was certain the tank had experienced a spike in ammonia several weeks earlier that burned the fish, leaving it vulnerable to infection. What caused the system to get out of balance? We think it was a combination of factors. First, the fish has been growing, but its tank has not; at nearly 7 inches, we should have had it in a 20 gallon tank, not a 10 gallon tank. Second, I think when we moved the fish tank to its new spot, we started inadvertently feeding the fish more often, since it was in a high traffic location. More food = more poop, and that means more ammonia in the system.

Mr. Fish Expert assured us that therapeutic levels of salt (4%, or 1 teaspoon per gallon) would kill the bacteria and help the fish heal, and scolded us for our over-reliance on Internet research. It seems counter-intuitive to put a freshwater fish in salt water, to say the least, but it seemed worth a try. Now, as you might have guessed, salt is not a good thing to have in an aquaponics system; even a small amount will kill your plants. So, we moved the fish to a "hospital tank," otherwise known as a lobster pot, and administered the treatment. Sure enough, within 48 hours the fish had more energy; within a week, the spots had vanished.

Now our system seems back in balance. We've upgraded the tank size, adopted a strict feeding regimen, and we test the water for ammonia frequently. Our rescue fish seems to have pulled through once again.

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