I thought these
statements by Dan Underwood, although they are based on anecdotal evidence, to be very interesting. They partially answered a question for me as to why so many people may have had better luck over the years with their horses at lower temps, when seahorses live in such highly variable temperatures in nature. Most species live in lagoons and grassflats where the temperatures can be hotter and more variable than the surrounding reef!! -which is incredible considering new insights on just how warm and variable in temperature the reef can be. The following posts are a very interesting discussion following Ron Shimek's article concerning just how warm and variable the reefs are. The stable temperature environment of coral reefs is a big myth- especially read the posts by
greenbean36191:
http://www.reefcentral.com/forums/sh....php?t=1869167
http://reefcentral.com/forums/showth...ht=temperature
Some species of horses are obviously from more temperate oceans. Even
Hippocampus erectus however, a "temperate species" lives in colder water throughout most of it's range, but it ranges from Nova Scotia, all the way down through the Caribbean and down into South America!!!! If this really is the all the same species (which I don't think there is any reason to doubt), it would be interesting to know how much "hardwired" genetic differences with regard to temperature there are among different populations of this species. In other words, does it matter if your
H. erectus came from Nova Scotia or Venezuela? Can a seahorse acclimate to a temperature range that is somewhere within the absolute thermal limits for its species? In nature
H. erectus must be living in temperatures from the low 50's to the mid-to high 80's across its species range!! Also, from what we know of daily temperature fluctuations on the reefs (to say nothing of the even more extreme lagoons!!), temperature swings of >4-5 degrees in an hour are not uncommon. Many of us reefers would literally freak if this happened in our tanks but a huge body of research and experience is showing it really isn't a big deal, and is actually beneficial as it acclimates our creatures to a healthier temperature swing in preparation for when something might go wrong- and saves on energy costs!!
I am not advocating doing any of this in a seahorse tank. Just trying to reconcile what I see as a big discrepancy between the conditions necessary for healthy wild seahorses and healthy captive seahorses. I see Dan's comments above as a possible step in the right direction to understanding this. That the change in diet and perhaps other conditions in captivity make our horses much more prone to mortality at higher temperatures, temperatures that they would otherwise thrive in as they can and do in nature.
As a closing thought, consider that back in the day people believed that keeping SPS in captivity was practically impossible. Advances in husbandry including keeping very, very unnaturally stable temperatures (e.g. +/- 0.5 degrees) have allowed hobbyists to excel at this endeavor. Now that many other requirements of the SPS are being met (e.g. better lighting, filtration, etc.), the temperature stability and maintenance of lower temps (around 76 degrees) have been shown to be unnatural and completely unnecessary for success. I suspect this more conservative temperature regime was simply a band-aid for something else lacking which now is not needed...
Questions?, comments?, experiences? Please no fights- and this is not a justification to do something irresponsible with your tank occupants- but to understand in order to be more successful moving forward in the hobby.