Planted Tank Guru
Join Date: Jul 2010
Location: Pflugerville, Tx
Before ordering I would look at picking some up from a local welding supply. For the really small price of washers, I can't think of it being practical to pay shipping.
For the question of getting them tight, I often find it is a problem with the wrench used as much as the washer. Almost anybody can get the fitting tight enough if a good healthy sized wrench is used. But then there are those special wrenchs put out that claim to be designed for tank use! The best thing to do with those is throw them away as they are simply not good for most of us to use.