Thank you, Ekona ………… yes, I think an age of about 4 month sounds very plausible. This is about the time that my nagyi-young needed to grow up to a similar size and colouration.
But nevertheless, when reading all the reports here in this forum on the rearing of fry of the most diverse species or forms, I have got the impression that the growth rates are very different, indeed – depending on various factors, as Peter already concluded.