[RayChez1]

Well! It is not suppose to be done that way because the two tanks are not the same size and if the shower or bath tub water goes into the black tank, it would not take long for that tank to fill up.

Example: My coach has 65 gallon grey tank and a 45 gallon black tank. Manufacturers will usually put two tanks that will equal the amount your fresh water tank will hold. My coach holds 100 gallons of fresh water totaling the same amount the two combined grey and black tanks hold.

There is no reason why a black tank should ever plug up if you use the proper amount of water it is suppose to use. And if you use Happy Camper it turns all your solids back to water, so when you dump most all your solids have been eaten by the enzymes in the tank.

I believe your motor home the previous owner had the plumbing changed after he bought it, because they are not suppose to come out of the Gulf Stream factory like that.

Your black tank will be filling up within three days of normal use.

Now what some RVer's have done when they dry camp a lot is to connect an overflow from one tank to the other so that if one tank fills up too quick, it will over flow to the other. Only bad thing about that is that if you get negligent and the tanks over fill, then you are going to have waste coming up the drain of your shower.