I’m seeing more and more of this.. this is not what you want to do.. even the barrel companies are making videos like this.. You want to fill one by one from an over flow in the tops.. you don’t want equal amounts between all barrels.. you want as much water in one barrel as possible so that you maintain pressure when coming out.. you also don’t need a breather.. you simply use the what would be the last overflow to fill the next tank that doesn’t exist in place to drain out.. When you do this from the top you push air from one tank to another naturally through each overflow till the water reaches that level then next tank one by one.. your final overflow becomes you breather and overflow vent at the same time.. this is the proper way to do this.. Second you then build a one way manifold off the bottom spouts that flow back to the main tank through a hose splitter.. This means you fill one tank at a time keeping constant pressure at all times.. drain one tank at a time in reverse keeling constant pressure until the first tank is being drained.. The end result is a lot more pressure and no longer a need for venting the tops of each tank just the system as a whole.. making a 2-3-10 barrel system as as a single large barrel instead of multiple have filled barrels
