whats the warmest someones kept them? and whats your breeding setups?
As Mattiej & Zoodiver have stated Chain Catsharks shouldn't be kept at temperates warmer than about 65F. While I've heard of people hatching juveniles at about 70-75F. This really isn't recommended - Chain Catsharks are a cool temperate water shark. As it has already been stated - water temps of 70F or higher will likely shorten the natural life span, or increase the risk of disease for any chain catshark kept at these temps. Inspite of the fact that they are found from New England to Florida - Chain Cats are a cool temperate water species.
The reason - the warmer the surface temperature is - the deeper the depth chain catsharks seem to be found at. Iin New England waters- where surface water temperatures (in the summer) rarely exceed 65-68F - Chain Catsharks are usually found at a depth of at least 15 to 40 meters(50 - 131 ft) . In Florida waters - Chain Catsharks seem to prefer depths of about 150-300 meters (490-980 ft) or more.