Noticed Fertilized Essence does not contain any NBT tags and as such cannot be filtered or voided using tags.
Steps to reproduce:
Put Fert Essence in a barrel/storage
attempt to move/filter the fert essence using any tag filter from your pipe/transport mod of choice(LaserIO, Sophisticated storage, etc...).

More Info:
Putting the essence in a Sophisticated Storage advanced void upgrade, setting the upgrade to "TAG" mode and placing a fertilized essence in the tag filter shows it has no tags to add to filter. Placing any other Myst Ag essence in filter shows it has the "essences" tag. Applying the essences tag from any other essence does not result in Fert essence being filtered. The only work around I found is with the Sophisticated Storage filter/void upgrades, setting them to "MOD" mode and placing a Fert Essence in the filter results in proper filtering/voiding.