When to add live rock to grow out tank?

[beertech]

Hey, just like the title says,
I have a small group of Maroon clowns that are now about 18 days old. They are in a new 10 gal grow out tank with just a sponge filter. I'm wondering if and when its ok to add some live rock to the tank for extra stability.
Thanks

 

[Navanax]

I would recommend not adding live rock that early, for reasons of cleanliness as well as stress. I siphon any detritus out of grow out tanks daily, if not twice daily; typically rocks and such get in the way and moving them out of the way to siphon stresses out the livestock. To account for the detritus lost to the depths of the live rock, more water changes would need to be done.

When is the best time? In my experience it's fine to add rock after the juveniles have been settled for at least a few weeks. Settlement is very hard on most larvae, so sufficient time should be allotted for growth to allow them to handle changes to their environment.

 

[beertech]

Thanks!
So how about plumbing the grow out tank to a sump below with live rock? obviously I would have a fine screen over the overflow and very slow turnover rate.

 

[Navanax]

Yes! that would be absolutely fine. just remember not to add too much at one time, it could cause too much fluctuation.