how do you keep sewer tank clear

Before our trip, we put about 3 gallons of water in the black tank with a Cup of Borax powder and a Cup of Calgon liquid and let it swish around on the way to the CG.

If you use anything other than lots of water, try The Geo Method. On the road I do this once a month. On regular seasons twice a year.

DO avoid treatments with Formaldehyde. They leave a residue that messes with the sensors. It's not a coincidence that the company that sells these products (starts with C ends with O) also sells sensor cleaners.

I try to drive a few miles before I dump ,easy for me because I mostly dump at my home base .

Water is key. If you don't have the outside hose thread to put in water while you are dumping, does your bathroom have a window? If so...run a hose in and rinse from top down..if no window, walk a hose into the RV, into the bathroom and rinse, top down.

After you are done and buttoned up? put more water into the tank. More than a little...be generous. Whatever you flush down the toilet, will turn to liquid. No sludge.

Gary Haupt

Been living in my rig for 3 years, use nothing but water, dump prior to moving on leave about 10 gallons of water in the tank until I reach my next destination.

We don't put solids in the stool unless absolutely necessary. Try to get sites not too far from the bathroom. Saves a lot of problems and worries. We use Thetford chemical for lubrication and odor but don't know if necessary.

It's easy. Drink a lot of beer.

We've been sitting in one spot now for a hile. We use two or three toilet tank treatments. We have the built in flush system like many do and hen tank gets near full, we fill the gray water tank,which flushes the hose essentially.
Fill and drain black and let clean water flow for five minutes after it drains. Close drain, Put in two or three of gallons of water, factory says to put in about five release the gray water and let clean water flow for five minutes.gallons. tie
Not sure it is needed but before last time we drain, will add some soap and softener and maybe ice to two or less gallons or so of water. When we next settle for the night, next day flush again.
Being pro active. Hopefully it isn't needed though.

We use Walex Bio-Pak and Porta-Pak tablets. These keep the black tank contents dissolving fast and remove the odor. I then use the black tank flush after the final black tank dump to keep it clear.

We camp mostly over weekends and dump as we leave the CG. So checmicals don't have enough time to break down anything.
However, I still use chems. Why? Because I don't want to be "that guy" that stinks up a city block while he's dumping. The few cents it costs is insignificant.