Are you absolutely certain it is the
Glyptoperichthys gibbiceps which have bred?
Normally a pair isn't mature until they reach 10" and then to breed they build a nest which consists of a tunnel dug out of the mud of a river bank and which extends for up to a metre in length.
They also lay about 1000 - 3000 eggs on average.
It would be very rare indeed for those fish to breed in anything less than a tropical pond.
Well done if it is those though.