Bottles are the 16.9 oz water bottles.
Rotifers are actually beneficial for you tank in a bit more direct way than phytoplankton as they feed the predatory corals and some fish directly. Phytoplankton is eaten by filter feeding corals and clams. It is not ingested directly by fish and must be fed to rotifers, coepods, or other "critters" to benefit predatory corals and fish.
They both fill very important food chain gaps and their use has been proven to increase fish and coral growth and coloration.
As for links I suggest searching this site as it has tons of great articles or read the sticky post at the top of the fish breeder forum.