I agree with Richard for the most part.  Let me explain:

1. I have a Massive collection I did myself or my mom and dad did with me.  I was a education and work project.  Wonderful time.  South Pacific Military base.  Ultra Rare species. :-)

2.  When I installed a 300 gallon salt tank (went down during covid - sad) and used some bags of "Live Sand"

where the sand comes from around the world in a sealed plastic bag and contains bio within.  Water within - I think just a scoop of sub beach. If Egg collecting is ok this way - buy some, hatch out some and you are growing them from egg level or very young fry but likely egg only.  All sorts of bio products are in a bag.  Go to a salt water store - some on-line. Buy a bag and put it into a tank and wait to see.  It was interesting as I had some float into the filter tank 100 gallon under the main tank and grew there.

Martin