It’s no secret that i am fond of keeping fish, and I like to keep them properly, in appropriate environments that enhance the health and well being of the animals, rather than using ugly-colored rocks and lame castles.
It’s also no secret that I’m value-conscious. I don’t like paying a lot of money for a tank that loses value faster than a new car driven off the lot. If I find value in a piece of used hardware, I will buy it.
Part of my master plan to keep the different species that interest me is to set up species tanks. I keep Endler’s livebearers (Poecilia wingei). Anyone who has ever kept any livebearer species in proper conditions will tell you that they are very good at breeding. Guppies (Poecilia reticulata) are not called “million fish” for nothing.
To effectively keep a livebearer species requires a minimum of three tanks. (1) Fraternity tank, where all the males live. (2) Sorority tank, where all the females live. (3) Honeymoon/Fry-rearing tank. If this method isn’t followed, you will have more fish than you have space.
With that in mind, my Endler’s livebearers had been all kept in the same tank, a 46-gallon bowfront tank that is the most visible one in the house in what is known as a colony. I kept them as a colony to grow my population from the original 8 fish to what ended up being a very large number–several hundred. All that in 4 months.
My plan had always been to segregate the fish once I had a decent sized population. Because the males are far and away some of the most colorful freshwater fish on the planet, they get to stay in that show tank.
Earlier this year, I purchased a double-decker wooden stand with two 29-gallon tanks. The females went into the lower of those tanks. Problem was, I had no tank for the fry. I picked up a used 10-gallon tank at Goodwill on 50%-off saturday, putting the tank at a steep discount of 50 cents per gallon.
I prefer not to pay more than $1 per gallon if possible, and especially if all I get is the glass. It turns out that this tank had been resealed with silicone that was meant for caulking bathrooms, not aquaria. Bathroom silicone contains an anti-mold chemical that makes an extremely effective anti-fish chemical, too. When I moved my fry into that tank, I started losing them.
Consider that these are very resilient juvenile fish. I have scooped up a dozen and they lived in a plastic bag for 12 hours without any ill effect. I dropped a very young fry into a brackish tank with specific gravity of 1.008 without any acclimation whatsoever, because I expected the fish to be eaten within 3 minutes. The fry turned out to be too fast for my gobies and is still alive and doing well in that tank 3 weeks later.
The fish kill had me completely perplexed for several days. New water, new substrate, new filter, new filter media, new heater, new air pump, and planted. An extremely clean system was killing fish. They died with symptoms of poisoning despite not having enough time to build up ammonia, and despite treating the water for chlorine. Those symptoms include clamped caudal fins and shimmying in place.
I couldn’t figure out the root cause until I stared at the tank long enough to notice the silicone repair job, and it made sense. My fish were dying because somebody did me the favor of fixing the leak with toxic silicone.
Once I figured out the problem, I moved the fish out of the tank and into breeder nets in both good systems. Most of the fish recovered completely once in good water, though some seem to have permanent damage.
I bought a replacement tank brand new ($1 per gallon so I am happy) and also replaced the substrate. Seven fry were moved in a good 10 hours ago and are still swimming like healthy fish. The toxic tank has been given to a person who keeps snakes (dry tank).
So, lessons learned:
1) Most fish health issues can be traced to water quality problems.
2) Fish don’t die for no reason.
3) Inspect used equipment closely.
4) If fish start dying in a new tank, get them out of there until you understand why.
I was lucky, I didn’t lose all my breeding stock and i have sufficient unaffected females to rebuild my livestock supply. And I did manage to use the bad tank to demonstrate proper syphon techniques. See yesterday’s blog entry.
