I won't bore everybody with a massive long story but basically I have a colony of 7 adult l144's and most of the babies are dissapearing.We had a batch of 40 babies that we put in a 60 litre tank 2 months ago , 6 left , only 2 bodies.

From the big tank we've had 3 or 4 spawns in the last month , around 70 odd babies loads have gone missing , no bodies , alien abduction ? are the parents eating them ? I can understand losing 10% naturally but where are they all going ? and why no bodies ? I know other people on here breed them but do they get this sort of mortality rate or have any ideas ? cheers

It is an unusually high mortality rate and I'm assuming there are no other tankmates who might be to blame.

Bn's will eat the body of a dead fish and could explain why your not finding any but it would be very unusual for adults to actively hunt them. Is there a chance they are getting drawn into the filters? Do they have food available at all times?

More details of tank set up, water parameters and feeding may help in finding a reason.

it is a high death rate but it does happen, more commonly with albino and related morphs.

The reason you are not finding any bodies is that they are being eaten by the other fish. This is quite often how the mortality rate can be sustained so high. High protein levels from eating too much meat, or illness being passed from on fish to the other. This is why daily water changes become so important, if a fry dies it needs to be removed ASAP!!!

More details as Jim said will help with IDing the original issue.

Yes they are being abducted by aliens. Happens all the time mate so your not the first. Damn aliens just gotta make our hobby even more difficult than it already is