Phyto's and filter socks.

[GaryZ]

Anyone know if phyto-plankton is small enough to make through your average aquarium filter sock? Say, 100 microns.

[Ninong]

The typical species used in phytoplankton products for reef aquaria are certainly small enough.

Here is Premium Aquatics' description of the three species of unicellular algae that make up D.T.'s:

"DT's is now a blend of three species phytoplankton. Two species of Nannochloropsis ; N. oculata at 2-3 microns, and N. salina at 4-8 microns, along with Chlorella sp.at 5-12 microns."