I don't want to sound like a complete Dumba*se Ray (just a lttle one) but I don't remember seeing a female socket anywhere underneath where the tank may hide it, and which would fit the one described

I have seen (I'll have to take a photo when I'm not at work) one (or is it 2) other female sockets but not the one you describe.
In saying that, when I get a chance tomorrow, I'll now have a good look for something that resembles a socket that will fit it, now that I have been told specifically which one does fit.
thanks buddy