I got two weeksii in june of 2013. they were both about five inches so i put them in my grow-out tank. they are now about 7 or 8 inches and still in the grow out tank. they could go in the main tank at this point, but based on their feeding habits i dont think they would ever get any food. even at lights off they would be competing with two gluttonous teugelsi.
since i initially got them i have had 3 laps and 2 teugs go in the grow out tank. All five of those bichirs started off a little smaller and quickly out grew the weeksii and were graduated to the main tank.
ive come close to rehoming them a few times based on their slow growth-rates, but they are pretty cool looking and they seem to be really rare in the hobby.