The outdoor fish season is beginning to wind down here in Canuckistan. Nighttime temps frequently hit 10-12C, although most days still warm up into the mod-20's. I have now removed large amounts of excess hornwort, duckweed, hair algae and cattails from all outdoor ponds at least a couple times this year, will probably still cull more duckweed before the fish come out in a few weeks time.
My "sunniest" tank was stocked with 2:4 latipinna "ditch mollies" and the same number/ratio of Jordanella flagfish. All these fish are enthusiastic consumers of hair algae, which I often grab by the handful out of other tanks and toss in here. The surface is usually a solid blanket of duckweed, thinned ruthlessly all summer. Both species have produced good numbers of fry, which are easily observed when there is some open water after a duckweed cull. I'm sure that some fry were eaten, but neither of these species is particularly fry-predatory so I still have lots. Very successful stock tank.
Next is my Hoplo (Megalechis picta) tank, stocked with 2:4 sub-adults in the spring. Again, lots of duckweed, and I always leave most of it intact to assist in bubble-nest building. I've seen a couple nests, and occasionally a "boil" or "bulge" when a fish moves near the surface...but that's it. No idea what might be lurking in there, but hoping for the best.
Gymnogeophagus rhabdotus did their thing again with numerous healthy fry from multiple spawns easily seen. Unqualified success.
Green Swordtails got a bigger tank this year, roughly 350 gallons. I introduced about 40 youngsters in the spring, small enough that they all still appeared female. They grew well, and at least a few males are nicely armed with swords now, swimming amongst numerous fry. An unsurprising success.
Heterandria formosa has failed, mostly due to my carelessness in not culling the past few years. I love these little livebearers, but two summers ago I spotted two females and a single male that displayed severely crooked spines. Couldn't snag them out of the pond; although I euthanized them in the fall they were free to breed all summer. Last summer, at least a dozen or more showed this deformity, and I was only able to remove a couple, leaving the rest to pass on the bad genetics. The problem is that the fish are so small that by the time they are large enough for the crooked spine to even be seen, especially in a pond...they have already bred and produced more bad specimens. This year virtually every fish large enough to properly see is crooked to a greater or lesser degree. I will try separating out those few normal-looking fish and carrying on with them, but they are part of the same genetic pool and will likely throw many twisted offspring. Not looking good; a failure.
I set up one tank with 10 very small Desert Gobies (Chlamydogobius) which I purchased, quite uncharacteristically, on a whim when they were available. Everything I read indicated that these tough adaptable fish should do well outdoors in the summer; maybe they did, but I haven't spotted any movement in there at all. They are bottom-dwellers...and they were not much more than fry when I got them...and we always have numerous predatory insects in the outdoor tanks. I am hoping that some made it, but...no way to know right now. I will be PO'd if they are all lost.
My Cichlasoma dimerus are being the same buttheads they were last year. Two adult pairs in a 6-foot diameter round tank. I saw at least two spawns of eggs being guarded by adults, and on several occasions spotted clouds of wrigglers...but once again they ate every dang one of their fry! And, even in this larger tank, the dominant male keeps the subdominant one looking a bit bedraggled and battered. They will go back into the 360-gallon tank in the basement for the winter, where the cooler temps will keep them calm and unaggressive...and then I'm sure that next year the same aggression and fry-predation will re-occur. These guys are lucky that I like 'em...and I'm not sure why I do.
And then, finally, there are the Goldfish. I picked a half dozen biggish ones to go outside into the single inground pond;. They were chosen using a strict scientific methodology: the first six dumb enough to let me net them went outside.
There were also a similar number of smaller fish spawned last year that participated in this venture. The small ones grew like wildfire; the big ones grew even bigger; and there are new fry everywhere I look. Interestingly, one of last years newborns has, unlike his/her siblings, seemed to sustain the black markings interspersed over his gold body instead of losing them as all the rest have done. I'd love it if this one keeps the contrasting black permanently.
As an aside, I'll state that the Hypostomus laplatae I placed outdoors...one with the goldfish and one in each of the livebearer-only stocktanks...have done exceptionally well and look terrific. It's easy to tell which tank has a laplatae simply by the greatly-reduced algae growth on the inside surfaces. These fish are terrific algae eaters.
Finally...this year I experimented with cattails, which have flourished in my inground pond for years. I put 2 or 3 pots, each containing a single cattail tuber, into several of the stock tanks. They have grown and spread like weeds; the water in the tanks containing cattails is always clearer than in tanks without. On the rare occasions that I actually check nitrates it's usually imperceptibly low. I guess pulling a handful of giant rooted plants with foot-long tuberous roots out of the tank several times per year does a pretty good job of nutrient export. Best of all, cattails are so flexible and unaffected by wind that they withstand the strong gusts that are common in these parts much better than most other emergent plants. They easilly stand 4 or more feet above the surface of the ponds, look great, and bounce right back after a windy day tries to flatten them.
I typed this up basically as a lazy way of keeping a journal for my own reference. If anyone has actually read through all of it...well, thanks, I guess, but...don't you have anything better to do?
My "sunniest" tank was stocked with 2:4 latipinna "ditch mollies" and the same number/ratio of Jordanella flagfish. All these fish are enthusiastic consumers of hair algae, which I often grab by the handful out of other tanks and toss in here. The surface is usually a solid blanket of duckweed, thinned ruthlessly all summer. Both species have produced good numbers of fry, which are easily observed when there is some open water after a duckweed cull. I'm sure that some fry were eaten, but neither of these species is particularly fry-predatory so I still have lots. Very successful stock tank.
Next is my Hoplo (Megalechis picta) tank, stocked with 2:4 sub-adults in the spring. Again, lots of duckweed, and I always leave most of it intact to assist in bubble-nest building. I've seen a couple nests, and occasionally a "boil" or "bulge" when a fish moves near the surface...but that's it. No idea what might be lurking in there, but hoping for the best.
Gymnogeophagus rhabdotus did their thing again with numerous healthy fry from multiple spawns easily seen. Unqualified success.
Green Swordtails got a bigger tank this year, roughly 350 gallons. I introduced about 40 youngsters in the spring, small enough that they all still appeared female. They grew well, and at least a few males are nicely armed with swords now, swimming amongst numerous fry. An unsurprising success.
Heterandria formosa has failed, mostly due to my carelessness in not culling the past few years. I love these little livebearers, but two summers ago I spotted two females and a single male that displayed severely crooked spines. Couldn't snag them out of the pond; although I euthanized them in the fall they were free to breed all summer. Last summer, at least a dozen or more showed this deformity, and I was only able to remove a couple, leaving the rest to pass on the bad genetics. The problem is that the fish are so small that by the time they are large enough for the crooked spine to even be seen, especially in a pond...they have already bred and produced more bad specimens. This year virtually every fish large enough to properly see is crooked to a greater or lesser degree. I will try separating out those few normal-looking fish and carrying on with them, but they are part of the same genetic pool and will likely throw many twisted offspring. Not looking good; a failure.
I set up one tank with 10 very small Desert Gobies (Chlamydogobius) which I purchased, quite uncharacteristically, on a whim when they were available. Everything I read indicated that these tough adaptable fish should do well outdoors in the summer; maybe they did, but I haven't spotted any movement in there at all. They are bottom-dwellers...and they were not much more than fry when I got them...and we always have numerous predatory insects in the outdoor tanks. I am hoping that some made it, but...no way to know right now. I will be PO'd if they are all lost.
My Cichlasoma dimerus are being the same buttheads they were last year. Two adult pairs in a 6-foot diameter round tank. I saw at least two spawns of eggs being guarded by adults, and on several occasions spotted clouds of wrigglers...but once again they ate every dang one of their fry! And, even in this larger tank, the dominant male keeps the subdominant one looking a bit bedraggled and battered. They will go back into the 360-gallon tank in the basement for the winter, where the cooler temps will keep them calm and unaggressive...and then I'm sure that next year the same aggression and fry-predation will re-occur. These guys are lucky that I like 'em...and I'm not sure why I do.
And then, finally, there are the Goldfish. I picked a half dozen biggish ones to go outside into the single inground pond;. They were chosen using a strict scientific methodology: the first six dumb enough to let me net them went outside.
There were also a similar number of smaller fish spawned last year that participated in this venture. The small ones grew like wildfire; the big ones grew even bigger; and there are new fry everywhere I look. Interestingly, one of last years newborns has, unlike his/her siblings, seemed to sustain the black markings interspersed over his gold body instead of losing them as all the rest have done. I'd love it if this one keeps the contrasting black permanently.As an aside, I'll state that the Hypostomus laplatae I placed outdoors...one with the goldfish and one in each of the livebearer-only stocktanks...have done exceptionally well and look terrific. It's easy to tell which tank has a laplatae simply by the greatly-reduced algae growth on the inside surfaces. These fish are terrific algae eaters.
Finally...this year I experimented with cattails, which have flourished in my inground pond for years. I put 2 or 3 pots, each containing a single cattail tuber, into several of the stock tanks. They have grown and spread like weeds; the water in the tanks containing cattails is always clearer than in tanks without. On the rare occasions that I actually check nitrates it's usually imperceptibly low. I guess pulling a handful of giant rooted plants with foot-long tuberous roots out of the tank several times per year does a pretty good job of nutrient export.
Best of all, cattails are so flexible and unaffected by wind that they withstand the strong gusts that are common in these parts much better than most other emergent plants. They easilly stand 4 or more feet above the surface of the ponds, look great, and bounce right back after a windy day tries to flatten them.I typed this up basically as a lazy way of keeping a journal for my own reference. If anyone has actually read through all of it...well, thanks, I guess, but...don't you have anything better to do?
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