My vote is that it is the A/C condensate - should be a tray under the units (you probably have 2) with a hose going to the shower sump - was disconnected from the sump when I bought my 39'. Short of that, on Miss Cleo that area has an abundance of thru-hulls, hoses, filters, and pumbing of all sorts - could be any of them. A thought - turn on your A/C units and verify that no water is leaking from the input cooling water filters - I had to replace the cover gaskets on mine.
Also, on Miss Cleo any water that drains from the anchor rode ends up there (minus the amount that can be pumped by the forward bilge pump) so if you anchor a lot ..... I have plans to install small bilge pumps fore & aft to get more of the residual left by both the forward and aft bilge pumps.
Richard