I got half a dozen dwarf chain loaches to compliment my 6ft community tank... And the stupid things have spent more time in the weir and the sump than they have in the tank.

I literally just fished three of them out of the sump, and the second I put them back in the tank one went directly to the overflow and straight in to the weir again. At some point it'll reappear in the sump.

I don't even think they'll grow big enough to stop being able to squeeze through the weir guard so I guess they live in the sump now.