I can’t be the only one with a poorly designed black tank.

Fill black tank from inside the camper i.e., use a hose and stick in in the toilet close the toilet on the hose and start filling. On mine, with a 40 gallon tank I run it 11 minutes then drain.

I do this for about 4 to five cycles or until the water is running clear.

When filling from the toilet you should clear out the shelf.

Truely not a aftermarket design to benefit the buyer.

That is why we adapt, improvise, apply.....