If you have Occellaris clownfish, their long-term lower temperature limit is reportedly ~75F (24C); at 75F and above, there’s no problem.* If the temp is slightly below 75F, you may not see problems unless they stay at that temp for a few hours/days. For immediate damage to occur from temperature, the temp would likely need to be somewhere around 59-65F (15-18C).**
Some tips in this related thread:
I've recently been doing a lot more research into power outages as I stock my tanks with expensive torches. With severe weather events and fires only increasing where I live, I think it's prudent to prepare for when the lights go out for extended periods or if I need to evacuate for a number of...
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*Source:
The physiological response of the common clownfish, A. ocellaris, to factors pertinent to air transportation conditions was studied in three stages: (…
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**Source (Fig. 3 is the relevant data):
The clownfish Amphiprion ocellaris is widely distributed in the coral reef ecosystems of tropical and subtropical regions of the West Indo Pacific, an area that hosts economically valuable species, and, thus, a suitable candidate for warm water aquaculture. This study determined the preferred...
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