This is a blog post I hoped I would never have to write. To my tester friends, this has only peripheral relation to my testing career, but it’s something I’ve been dealing with for the past several days, and it’s taught me a few things, and reminded me once again of several things I thought I already knew. Normally, I take a somewhat self-deprecating tone with posts like this, but I’m really and seriously bummed about this, so I’m just going to tell it straight without any jokes or color commentary.

Yesterday, my 70 gallon fish tank became a ghost town.

This tank has been up and running, in some way, shape and form, continuously, with one major exception (for a swap-out back in 2007 due to a ruptured seam) for 19 years. In that 19 year period, many fish have come and gone, for a variety of reasons (personal taste and interest, changes in water chemistry moving from soft, acidic San Francisco to hard, alkaline San Bruno, etc.). Generations of fish have been born, grown, given away, and repopulated to other tanks. It was a vibrant community of predominantly cichlids, though it has housed other fish over the years as well. To put it simply, it’s run pretty much flawlessly, and without much in the way of tweaking and meddling on my part, for years. That all changed Monday the 11th of November.

Wait, let me step back another few days, to Saturday, November 2, 2013. That day, I did something momentous, and potentially provided the catalyst that started this whole thing. On that day, I made a decision to end a decade long experiment. I’d kept a breeding colony of Convict Cichlids (Archocentrus nigrofasciatus) running in that tank for that time, and it was successful. In fact, it was too successful. I had run out of tanks to house them, and shops willing to take them (even for free; I was flooding the local market with Convicts). With no more room to put them, I decided it was time to make a change. I kept the largest and longest lived males, separated out all of the females and juveniles, and with a final “special delivery” to my favorite fish store, I brought the breeding colony to an end by bringing those females and juveniles to the shop. Yes, we’re talking dozens of fish.

In the process, I noticed that they had some new arrivals, in particular several Green Terrors (Aequidens rivulatus). Contrary to popular folklore, the name is a bit of a misnomer. They are cichlids, so yes, when they are in “breeding mode”, they can be as aggressive as any other cichlid species, but no more so. As I was looking at them I though “wow, what a great time to balance out the tank with a new species”. With Acara (Green Terrors being part of this family of cichlids) and Convicts, as well as my main tank denizen, a Green Severum (Heros efasciatus), coming from similar waterways in Central and South America, I figured they’d be a great addition to my tank. I bought four of them, introduced them into my tank, and then spent the next couple of days getting ready to go to Sweden. Since I was going to be gone for awhile, I figured giving the tank a good thorough cleaning and larger than average water change would be good for all involved, as well as a perfect time to introduce the new fish.

Now we fast forward to Monday evening, November 11th. As I came home from work that day, my younger daughter said “Dad, there’s something wrong with Kite!” Kite is the name for the large Green Severum; he’s really placid and just drifts around the tank like a big kite, hence the name. I asked what “wrong” meant. She said that his whole body looks like someone poured salt all over him.

Uh Oh!!! I know what that means. We have an “ich” infestation.

Now, I’ve seen these before, and I’ve treated them in the past, so I figured, well, this shouldn’t be too big a deal. Since I’d needed to get medication anyway, I figured I’d pick it up the next day and start treatment when I got home. For good measure, I’d do another large water change so that I could limit the spread of the problem. Unfortunately, my hospital tank was not set up. Even if it was, I’d need a larger tank to put the Green Severum in; a 6 gallon quarantine tank isn’t going to cut it for a 10″ fish! Therefore, it meant I’d have to treat the whole tank. Turns out that would have to be the main step anyway, since when I got home, I noticed that the signs of the disease had spread to several of my Convicts as well. With that, I started measuring out the medicine and dosing the entire tank. I also followed the directions and removed all of the carbon and chemical filtration materials from the filters.

Within three days, I saw that almost all of the fish were erupting with the parasites and the tell tale signs on Kite were becoming even worse. He looked like he was coated in a layer of plaster that was cracking away, and his fins were decaying at an alarming rate. With that, I knew it was only a matter of time. Some of the smaller convicts were the first to go on Wednesday, then some of the larger Convicts followed suit. Kite, my oldest and longest lived veteran of my tank, at 12 years, succumbed to the disease on Friday morning. Over the next three days, roughly every twelve hours, another fish would die until finally I was left with only three fish. Looking at the two surviving Green Terrors (two had likewise died during the week), and my longest lived male Convict, I took a look at the two Green Terrors and realized that, if anyone were likely to survive, they had the best chance. With that, I set up the 6 gallon hospital tank, and pulled them out to be monitored and treated. My oldest Convict, I had to leave him in the big tank, and hope for the best. Alas, the end came for him too, last night. As of now, there are no fish of any kind in my main tank. They are all dead.

As of this morning, my two Green Terrors are still holding on, one looking like it might be a hard recovery (he’s lost a fair amount of scale over the left side of his head and flank), and the other having what looks like a real fighting chance. My 6 gallon tank is not much, it’s definitely not the environs I just pulled them out of, but it will have to be home for the next three weeks, and on the plus side, they are currently still alive. For the first time in 19 years, though, my main tank is now devoid of life, except for what may well be a colony of parasites that I will now wait out the next three weeks, to make sure that they are all dead before I try to start the tank up again.

Many things have been going through my head since this all happened. What did I do wrong? The answers are telling. Most critically, I broke one of my most important rules, and I did it out of impatience. My hospital/quarantine tank wasn’t set up. It hadn’t needed to be for some time. I was not prepared, and I didn’t have the necessary materials in place. Cautious, intelligent me would have set up that tank first, and would have let it cycle for three weeks, then bought new fish, and had them wait in the quarantine tank for three weeks, before introducing them to my main tank. Instead, because of a moment where I was making a major change in the ecology of the tank, I figured “why not?”, and I just added them to the tank. What’s the worst that could happen? I really hadn’t imagined “the worst” would mean “wipe out my entire environment”, but yes, that is exactly what happened.

Was it just the introduction of the fish? If that’s the case, why were they not sick? Why did none of them show any signs of the disease? Could there have been another potential cause? Yes. Pretty much all fish carry parasites. It comes with the territory. “Ich” is expressed when fish have a stress episode, and those parasites are excited and act
ivated. They then push out of the fish to reproduce and look for new hosts. Could the two large scale water changes in less than two weeks have contributed to that? Well, yes, potentially. The fact is, water pH is probably the one thing, outside of ammonia or nitrite spikes, that will most stress/affect a fish. I try to keep the pH as close to 7 as possible, but when I checked the water late last week, the pH was 7.8 (and yes, that difference is significant). That large a pH swing could have triggered the change.

Could the medication have exacerbated the problem? Entirely possible. One of the dangers of mediating a large tank is that the dosing is very hard to determine. What would be normal for one fish might be too little for another, or way too much for a third. This is why it’s best to treat fish individually in a hospital tank if you can. Treating a whole tank can have wildly varying results. It’s also possible that the dosing of the tank was too late for Kite, who already showed advanced symptoms.

Could I have done anything different? Sure, and the last option is  the one that really makes me cringe, but I know the truth of it, and didn’t heed it. I could have left them alone. I could have resisted the urge to add some new fish to the tank after a major “depopulation”. I could have not bothered with the water change before leaving for Sweden. I could have let the disease just run its course. Yes it would have likely killed Kite, but he was 12 years old, already beyond his life expectancy, and having had a really great run. All sorts of coulda’, shoulda’ woulda’s, but no, the thought of doing nothing terrified me. I did what any irrational pet owner would do when their animals are in distress. I tried to fix it with all the tools at my disposal. The net result is a ghost town. Over a dozen valuable fish, but more to the point, fish that were good and dear friends I’d raised for many years.

Why am I mentioning all this? Simple, this is my blog. This is one of my biggest hobbies outside of testing, and one of the ways I observe and learn about the semi-natural world. Often in tanks, there are two things that are killers; overt neglect and over meddling. The middle ground is sometimes referred to as “benign neglect”, where we do the bare minimum necessary, and let them sort it out for themselves. I’ve never been guilty (at least not that I know of) of “overt neglect”, but yes, I’ve frequently been on the “benign neglect” scale. Sometimes, that’s just the best way to deal with things, but it makes us feel heartless when we do it. It seems this would have been a time where more “benign neglect” would have been far more beneficial. As it stands, I now have a recovery project underway. I will rebuild, and I will renew this tank. New life will take root here again, but sadly, it will be with a whole new family. All my “best friends”are gone, and they are gone because I over-reacted.

Update: I’m happy to report that both of the Green Terrors seem to be doing OK, even the one that’s missing half the scales on the left side of his head. He’s being feisty, sparring with the other Green Terror, and thankfully, he’s even eating, which means he really does have a fighting chance. I tend to name the fish that stand out in my tanks, and thus, if this little guy pulls through, since it’s likely he’ll have a bit of scarring that will look like a Pirate’s eye patch, I’m going to call this little fighter “Harlock” after Leiji Matsumoto’s legendary space pirate. Here’s hoping I can make good on that.

A grainy shot of “Harlock” in the hospital/quarantine tank.
I’m pulling for ya’, dude!!!