3 ms·I misread that as "(black water) tank" and got worried.by Zarathustra30 3y agoI misread that as "(black water) tank" and got worried.atoav 3y agoAll of Greece with mercenaries on their roofs. Strong houses they built.rz2k 3y agoBlack water also typically refers to waste water from toilets, as opposed to grey water which is waste water from baths and sinks.