Would you happen to have an in-line filter for the sinks ? Ours has an in-line filter which is supposed to be removed and replaced with a provided clear plastic tube the same length as the filter when you are running anti-freeze through the sink faucets. Don't know if the filter will stop the antifreeze or not, but manual says antifreeze will "damage" the filter.
2003 Ford F-350 V-10 Crew Cab 4WD Long Bed
2004 Jayco Designer Medallion 29 RLTS 5th wheel
Bill, Gayle, and Mindi (dachshund)
Retired at last !
Nothing is foolproof to a sufficiently talented fool.