Fry growth: with vs. without parents.

[flowerpower]

I recently had a GT pair spawn. From their brood I siphoned half to raise out separately and left half with the parents. Not surprisingly, the ones left with the parents doubled and tripled in size very quickly while the ones I removed not only grew much slower but took longer to develop. They were fed decapsulated BS eggs, Newly hatched BS and a powdered flake/BW/pellet mix multiple times daily while the ones w/ the parents received only BS hatchlings and whatever the parents could provide. The fry that were left with the parents were eventually eaten but the ones that I separated are slowly but surely growing up with no apparent losses.
My question(s): Is the reason for their slow development nutritional and, if so, how can I replicate what they get (chewed up food particles, mucus secretions) from their parents ?
My ridiculous theory: Could the slow growth of the fry be 'psychological'? Could the lack of parental nurturing be the cause of their decline in growth?I have considered introducing a fake fish as a kind of surrogate mother the next time I split a brood

 

[packer43064]

I have noticed this too, fry with parents will grow at least twice as fast as with fry in some other tank.

My reasoning was because mainly in the parents tank there is an endless amount of food, plus warmth and protection. Fry that are with the parents will scavenge all over the gravel, sand, etc. and just eat absolutely anything. I didn't even feed my fry and they did just fine. While in a new tank there isn't this food on the bottom for them to eat plus I bet their more stressed. They just swim around, absentmindedly because they have no parents to make them take for cover when a predator (us) comes by and spook them. So stress and the less amount of food is what I think makes fry without parents to grow much slower.

 

[flowerpower]

Thanks for the reply. And thoughts on inducing faster growth rates in separated fry?

 

[packer43064]

Try and have a aged tank already ready for them. Whether it be filled with guppies for awhile or whatever I think it would help alot. Pluis keep temps real high. Most fish can withstand 70-82, I kept my fry at a toasty 80 or more depends on the outside fluctuations. Feed often of course, weekly water changes of course but even daily would be better. Fry can be really fragile as little unns, once they get 1/4 in. their much more stable depening on the species.

 

[fsc46]

When I added a 7-8 inch koi with my cichlid fry they started to grow really fast. It may have something to do with it stirring up the substrate. Not sure though.

Thanks for the reply. And thoughts on inducing faster growth rates in separated fry?