In message , sophie
writes

snip

Many thanks to NetMax and Cris - fantastic advice and I shall follow it
(why on earth didn't I think of filling the tank in the garden first? -
sheer brilliance, thank you.)

I'm not sure what the seller was doing prior to starting on his own
aquatics business; I get the impression he was in the trade. I'll find
out more when I see him. I'm really hoping this is a good tank; I have
far too many fish in a small one at the moment (my LFS, frankly, lied to
me about how many goldfish I could keep in a 13 gallon and failed to
tell me they might eat minnows. I'm hoping that they don't get big
enough to do so during the minnows' natural life-span) and I need more
space! I've never kept fish before this and I want to give them a good
home.
--
sophie