I have never grown amaryllis from seed, so just for fun decided to give it a try. I floated some in water and put some in soil. The ones in soil already have foliage. I did not spread them out very much when I planted the seed because I really didn't expect that they would do anything. So, when should I separate them or should I leave them in this pot? BTW, the ones floated in water have a short root but no foliage yet so not needing to do anything to them at this point. The foliage of the ones in the pot is somewhere around 3" long.

They look great and will be fine in that pot for a while longer. Eventually you can tease apart the roots and space them out a bit. Snarfie, who posts on this forum, has been very successful at starting amaryllis from seed. Check out his threads or send him a private email if you have questions about propagation from seed.

I agree that you can leave them alone for a while. They stay pretty small for a while. Also, I have have very bad luck when I have tried to transplant the seedlings, so that is another reason to just leave them be. My successful transplants have usually been a year old before I transplant them.