Gymno cool-down period

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Last year I tried running a sponge filter in one stock tank, with poor results. With no circulation, the sun beating down on the water heats the surface inch or so way up into the 80F+ range...but the rest of the water remains cooler and more amenable to the fish. With an airstone or filter, all the water gets too hot.

I was warned about this by someone here on MFK... C. Breeze C. Breeze I think. I was skeptical...this is up here in Manitoba...but it was true. I shudder to think what kind of temperatures you would develop down in your area. I have a few sheets of plastic lattice ready to provide some shade to my tanks if they overheat this summer.

Interestingly, this spring I checked last year's water in my inground pond, also completely devoid of artificial aeration/circulation/filtration. It is lightly stocked with fish each summer (like the stock tanks) but is overgrown with plant life (ditto). The water showed lots of tannin colour, but registered no detectable nitrate, nitrite or ammonia when tested. I actually used some of it this spring to mix with the snow melt water I filled the tanks with, to bring the pH and hardness more in line with the indoor tanks' well water.

I'm hoping for big things this year. :)
 
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Great thread. Do you have any type of filtration or air going to the vats? I have an 800 gal vat going this year currently and am scouring the site for ehat others like to do. My water Temps up to the mid 70s with just a couple hours of direct sunlight in alabama atm. Hornwort, ducked and wisteria have really taken off and kept everything in check thus far

i find that you have to be in the ground or have a large deck surrounding you and have full shade to keep things reasonable where I am in coastal Georgia if you run circulation. I’ve kept all My vats stagnant for a few years now. Even a 1000 gallon, if it gets any real sun becomes brutal by July / august. This year I’ve moved my group of wild missioneira pikes and my pair of wild Celido pikes to a 300 gallon that is being pumped with a 1200 GPH pump so that the current is basically continuous due to the roughly circular :oblong nature of the stock tank. And I’ve got bricks that make a wall and all kinds of hiding places. It is in full shade and I’m building an insulated box around it basically to keep it as cool as possible. So- I’m attempting current again due to its importance for the rheophilic pikes- and hopefully I can keep it dialed all summer. I will of course share my experiences and findings with the group.
 
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Ya know...some days it's just not worth chewing through the restraints to get out of bed...

After a morning spent chasing schools of pond fish off my flooded yard and back into the pond proper, thanks to over three inches of rain that fell yesterday...I meandered over to check my stock tanks, now all filled and overflowed. I had done some thinning a couple days back of the rampant Hornwort growth in them, and the overflow event had skimmed off a bunch of Duckweed that had survived my culling of it, so the visibility into the depths is now the best it has ever been or ever will be. The Swordtail tank was pea soup; it gets a lot of sun and this is typical, but I know that there are tons of fry of all sizes in there as they frequent the surface when I feed.

Then I moved to the others. I peered into the first (balzaniis); no activity visible, which still means nothing; lots of caves and still a fair bit of plant life in there. The second tank (adult Rhabdotus) had at least two adults clearly visible, and there seemed to be lots of "small life activity" among the plants, but this could be tadpoles, so...nothing conclusive.

The biggest tank is 360 gallons, and was stocked with 2 pairs of C.dimerus. It is slightly more shaded than the others, the water is crystal clear...and it is full of fry, of several different size/age groups. Unequivocal success...and high time...:)

The last tank had several dozen fry just under the surface, feeding amongst Hornwort. Great!...except...is it? That tank had been stocked with a number of surviving fry that I had snatched from the basement 360 after the fish began prematurely spawning in there, before I moved them outside. This included at least 6 G.rhabdotus fry that were close to an inch in length, plus an additional 5 or 6 more that seemed to be C.dimerus and another dozen that had been too small to even guess at,all of which were caught and removed from the indoor 360 over a period of days back in the spring. Hell, there might even be some balzaniis in the mix. The oldest fish, the rhabdotus, were from a spawn around the third week of March; all others are younger than that. So...where did these new fry come from? Could those rhabdotus have matured and spawned in only 4 months? Seems impossible...but there are new fry in there, and they were close enough to the surface that I could positively identify them as fish, rather than tadpoles or other interlopers. They're not even too small, maybe almost 1/4-inch in length.

I considered netting a couple out, but honestly, what would that tell me? I can't distinguish those three species yet at that size; and if one of the three has spawned in there, as unlikely as it seems, it simply must be rhabdotus (the oldest and biggest fish introduced). So I just left them there to let nature take its course.

I think I'm starting to remember why I was never an avid Cichlidophile: too stressful. :)
 
Just checked my laughably meager records, and the balzanii indoors were carrying fry at the beginning of March, so...maybe it's them. Still seems really, really young though...
 
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Spent some time today sitting quietly next to the stock tanks, taking advantage of the freshly-thinned Duckweed to look for fry. Since these cichlids all tend to be fairly bottom-oriented...the dimerus are the only ones I have ever seen eat from the surface, and that only rarely...I was using a pair of ultra-close-focusing binoculars and scrutinizing the lowest levels.

I have fry in every tank! Adult balzanii, rhabdotus and dimerus...as well as the rhabdotus grow-out tank! Those little sub-one-inch rhabdotus that were spawned this past spring in the basement have grown to maturity...saw one that looked close to two inches...and produced fry of their own. In a way, I am over the moon about this...but, on the other hand, I would normally have preferred the females to put on a bit more size before expending all that energy on breeding.

But, as I have said so often regarding other aspects of this hobby...don't fight nature! :)
 
Correction: the rhabdotus grow-out tank has at least two separate broods of fry, one looking at least a week or two older than the other. The two size groups school fairly tightly with their own, but the two groups didn't really intermingle while I observed them.

Hint: for those with outdoor ponds or stocktanks, I think that one of the best investments you can make would be a pair of ultra-close-focusing compact binoculars. These little gadgets are market to birders and especially to the subset of birders that is interested in "dragonfly-watching"...yes, that really is a thing. The pair I have is made by Pentax, and depending upon your individual eyes can be focused to produce sharp images of objects as close as three feet or less. This is perfect for standing next to a stock tank and searching the depths for fry. I even use them in my fishroom to closely study fish behaviour and activity while sitting comfortably in my armchair across the room.
 
I had to look for them for years before I could find them for sale locally, but we have very few decent aquarium stores in this area. When I found them, they...all three species...were quite inexpensive; I purchased all three species as young fish in the 1-inch range for $10 -$15 Canadian apiece.

The rhabdotus disappeared from the shop almost overnight; the dimerus have come and gone a couple times since then; and the balzanii were in stock for many months after I bought mine...I guess I was the only one looking for them...:)
 
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