First off, I have never said that issues people have at higher temperatures are made up. It is however more complicated than just higher temperatures kill horses.
I also do not generally recommend that people keep their horses at higher temps (though I see in reading back through this thread that I did not add the usual caveat).
Also, the horses are able to escape to a temperature that better suits their needs
While there are some species that have been observed to migrate, the few studies on seahorses and territories show that horses on average have a territory of between 6 and 20 square meters. That is, they occupy a small area and do not generally venture outside of it.
On top of this, in those lattitudes close to the equator, you need to go quite deep to reach a thermocline. When I dove the GBR in Australia the water temperature was a uniform 75F (winter temp.)from the surface down to 30 meters. Given that a species like H. Kuda is generally found in waters of 1 - 20 meters, its not likely that they would migrate to cooler water.
If you look at a shallow water species like H. kuda living on the equator, it is quite likely living in water that ranges between the low 80s and low 90s 7/24/365.
I also find it interesting that the folks running captive breeding programs in places like Viet Nam and China are running their systems at 78F. I have run across 3 such references so far. Two were definately in reciculating systems.
rather reality based on years of experiences and research.
I'm interested in the research part. Has anyone taken a look at bacterial concentrations, particularly vibrio, in horse aquariums and been able to compare them to levels found in nature?
Interestingly, In a paper by the folks at the Shed Aquarium written in 2002 they identified vibrio as the primary disease issue at their facility. However, the majority of cases occurred in the first two weeks after new specimins were acquired. They linked the disease to a compromised imune system caused by a lack of feeding as the horses passed through the distribution system.
So, while I believe that warmer water temperature can contribute to issues with horses, I
personally do not think that it is the primary cause.
At any rate, I will continue to run my system the same. Perhaps I will come to regret that, perhaps not.
To bring this back on topic for ratimpulse, I would definately not recommend running your horse tank in the 80s. I personally think you can run it a little warmer than the recommended 74 as long as you are aware of potential risks.
If you are going to run a chiller, you can dial your temp in where you want it.
Fred