Use a good biological agent such as TankTechs Rx or RV Digest-It to help liquify the solids. Use plenty of water when flushing #2. Don't empty the tank until it is at least 2/3 full. Given that the tank sensors are notoriously unreliable, you will need to estimate when the tank is full enough to dump.

While you are at it, look up TankTechs and view the various videos there. It will be quite informative and will likely be very helpful.

I use something like this that I got from Etrailer.com

Valterra Hydroflush Reverse Flush Adapter for RV Holding Tanks.   Item # F02-4100

Originally posted by lostagain In addition to using a really good digester/enzyme agent to dissolve the solid waste, another thing you can do to ensure better black tank emptying is to avoid putting paper products into the tank.  Though at first thought, it's gross, it makes emptying the tank easier.  We've been doing it for since we got our 172 and have never had a problem fully emptying the black tank.  Our method is similar to that seen in countries where plumbing systems are limited.  Simply discretely fold the soiled paper and put it into a small plastic bag to be thrown away in the trash like a dirty disposable diaper.

Yeah, that is gross.  1st through 21st thoughts.  More than that, it's unnecessary.  Plenty of water is the answer.  Have a few gallons in the black tank to start, flush the toilet with plenty of water, top of the tank before emptying it.

Why in the world have a plumbing system you don't use?  Problems can happen, but rarely with plenty of water.  Deal with the problems when they come up but enjoy having the fully-functional bathroom you paid for!

TT

I agree with OG that using the toilet facilities in your campground is a good alternative when they are reasonably clean.  We are on the return portion of the our trip across the country and stayed in many rest areas along the interstates.  Unfortunately, with the very high use and the limited cleaning, those restroom facilities were not as pleasant as they could have been and we used the head in our trailer for everything.  So we had to be mindful of filling the tanks too fast in order to avoid dumping along the way.  Folding a little TP is way less gross than frequent dumps in usually not too clean dump stations.

There is another element to the issue.  Those tiny rolls of RV TP are very expensive and the paper quality is, well I suppose one could say, uncomfortable, not to mention it doesn't dissolve all that well.  We use regular household thick soft paper and it not only is more comfortable, it folds nicely for discrete disposal in the little plastic bags.  No worries about having to clean out undissolved strings of paper trapped in the corrugated drain hose and fittings.  And if you like those so-called flushable wipes, the little plastic bag system accommodates their use as well.

It all boils down to personal preference, just like whether to use a WHD, a turbo or naturally aspirated engine, or eating your vegetables.  We each have our own way of solving problems and as long as we aren't hurting others and it works, go for it.