Black tank question

I travel in a similar manner. Because my black tank is so large (75g) it takes a long time to get it full enough to dump. I add a gallon or so of water during the week between weekend trips to account for evaporation and an extra chemical pack every 2-3 weeks (I use the purple ones that dissolve).

I usually dump at about 2/3s full and then let the tank sprayer run for 30-45 minutes, close the valve and reset the tank. This has been working without issue for me for many years.

get a black tank flush. I emptied my black tank at my convenience, didn't wait till 3/4 full, etc.
bumpy

Our travel over the years often included weekend trips to racing events, football games, etc., where dump facilities were not readily available. We frequently returned home with holding tanks partially full and no facilities for dumping there either.

I have gone several weeks before using the coach(es) again and find as long as we kept enough water/liquid in the black tank and drove as little as 3-4 miles before dumping that everything worked well. We always use a chemical in the black tank, and know some owners who don't, but I can't say this made it any better or worse as for the results I have seen.

My experience has been less positive when we are parked for weeks or longer, and dump the black tank every few days. The lack of agitation from driving down the road being the missing difference requires much more diligent flushing to keep the tank clean than when we are traveling and agitating everything constantly.

Others experiences may vary, but that's mine.

I use mine every weekend and NEVER empty it until it is at least 1/2 full.....Mine has a huge black tank.

I dump as often as I can when traveling. If it's below a 1/4 I add water to fill it and make the dump a cleaning event.

I 'never' leave a parked RV with anything in the black tank.

In fact while at the CG, a full tank of water is added after the dump and dump again to make the final dump before heading home or even back on the road.

Driving around with a half full tank of sewage and TP just makes it more possible for that TP paper to stick to the sides and sensors.

Tough one when use is so limited.
Our rule was "never travel with poop"
But sometimes it's not easy to get a good flush when there is little liquid in the tank.

I'd say let it get at least half full, unless it starts smelling kinda ripe.

Our current coach has a Techma macerating electric toilet and a sanicon macerater. This setup changes all the rules. No solids in the black tank.

Make sure there is plenty of liquid in the tank and empty when it's 3/4 full at least. If there isn't a significant amount in the tank when you empty it the tank will not empty fully and you run the risk of solids staying in the tank and solidifying even further. Just make sure there is a lot of liquid and that it doesn't dry out.

Just a suggestion, If you are only doing short, one-night stops: Get a porta potty. Another poster suggested using one and I decided to get one. The one I got, (Amazon) has two chambers. The top one, (for flushing)holds 3 gallons, the bottom reservoir holds 5 gallons.
It can easily be cleaned when you get home. My TT has a huge bathroom and I have room for it. It's about the size of the TT toilet.