There is some log spam coming from the fluid removal here, as it tries to remove fluids that don't exist in the forestry cans.
https://github.com/OmnifactoryDevs/Omnifactory/blob/830b55ab2cd3fd3e72b63ebc36377e5482312862/overrides/scripts/Forestry.zs#L89-L93

There should be some way to remove these fluids without causing the log spam