Aquatainer Hose Connection

I have the sewer cap with garden hose connection that I use to dump into a 7 gallon 'blue' tank on wheels. To connect the two I use a washing machine hose which has the female connecter on both ends. This hose mates up to both the serew cap and to the 'vent' hole on the blue tank. Or I could get another sewer/garden hose cap and use it on the blue tank. Either way works. You just need to make sure the receiving tank can breath when fluids flow into it.