General question regarding temps

[freshwaterfishfan]

Are there Apistogrammas which do not tolerate higher temps (mid 80's)? Are there some that prefer higher temps? I have a kind-of-greenhouse with aquariums that I would like to breed various Apistogrammas sp (mendezi, iniridae, wilhelmi) for now) but the water gets to the mid to upper 80's during the hotter parts of the summer. Stays 78-82 otherwises (except in the dead of winter when I would move the apistos to other tanks).
Let me know what you experts think.
Steve

 

[regani]

I am not an expert but my tanks get to about 90 F in summer and I haven't had any particular problems so far. I just make sure that there is enough water movement on those hot days so that the oxygen levels don't drop too far.

 

[freshwaterfishfan]

I am not an expert but my tanks get to about 90 F in summer and I haven't had any particular problems so far. I just make sure that there is enough water movement on those hot days so that the oxygen levels don't drop too far.

Thanks for the info - I tend to overfilter my tanks with large sponge filters so hopefully that will work. I will also try some floating plants to shade the aquariums a bit to see if that helps.
Steve

 

[gerald]

If the heat is coming from sunlight radiation it would be more helpful to shade the area surrounding the tank (with greenhouse shade cloth, cardboard, etc) rather than just the water surface. If the tanks are heating up from contact with the surrounding hot air (convective heat transfer, not radiation) then shading will not help. An open top with air blowing across the surface will help either way. Floating plants might actually work agaisnt you in that case.

 

[Mike Wise]

Yes, they can handle higher temperatures. Your only problems will be that the fish age faster and you'll get mostly male offspring. It might be worth reading: Römer and Wolfgang Beisenherz. 1996. Environmental determination of sex in Apistogrammai (Cichlidae) and two other freshwater fishes (Teleostei). J. Fish Biol. 48(4): 714-725.

 

[freshwaterfishfan]

Yes, they can handle higher temperatures. Your only problems will be that the fish age faster and you'll get mostly male offspring. It might be worth reading: Römer and Wolfgang Beisenherz. 1996. Environmental determination of sex in Apistogrammai (Cichlidae) and two other freshwater fishes (Teleostei). J. Fish Biol. 48(4): 714-725.

Mike, thanks. I had not thought about that...is the sex determined at birth or can temp change fry sex? Maybe I will use these tanks as grow tanks instead...
Steve

 

[freshwaterfishfan]

If the heat is coming from sunlight radiation it would be more helpful to shade the area surrounding the tank (with greenhouse shade cloth, cardboard, etc) rather than just the water surface. If the tanks are heating up from contact with the surrounding hot air (convective heat transfer, not radiation) then shading will not help. An open top with air blowing across the surface will help either way. Floating plants might actually work agaisnt you in that case.

Gerald, I might give that a try. It does seem to be direct sunlight from the top. I have fans circulating the air to keep the ambient temp as low as possible (low 80's).
Steve

 

[Mike Wise]

Sex appear to be set by the temperature during the first 6 weeks of life. In this case, once the eggs/fry are found, just adjust the temperature to the ideal 26°C/79°F. One can do this by adjusting the tank's temperature or moving the eggs/fry to a tank with a more suitable temperature.