Not a lot more i can add that hasn't been said - I had however read your 40l as 40 gallons
)
We used to breed our bristle noses in a 50l... it was heavily filtered though and needed regular water changes. definitely to a good idea to start out with.
if you have to have a plec in the 40l - have a look around for a bulldog or a clown (the maccus mentioned above) both stay small and look like plecs
we started our 'collection' with what was sold to us as a common ancistrus (bristle nose) it was small at less than an inch ideal for the 50l we started with.... 3 months later he was nearly 5" with no bristles... that led to the 190l... and now the 350 hes in. as he turned out to be the common Plec in our sig now about 12"
I've never posted any of the fish we've bred yet - but it can be done (and is regularly by user on here)
I prefer people collecting or meeting up (normally at a fish shop as we can all navigate to them
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