Best way to clean? Liquid Drano. That's what our KZ owners manual says to use. It won't hurt metal or plastic, including the seals. We use it from time to time to get the tanks back to factory fresh condition. Have used it for the 3 prior seasons. Problem is, it doesn't take very long before the sensors aren't working again. :(
The Horst Miracle probes may or may not help and it depends somewhat on the shape, dimensions and location of the outlet pipe. They worked great on a previous TT but hardly make a difference on our current TT.
After you've been using your tanks for a while, you get to know about when they need dumping. Looking down the black tank works - adding a shutoff valve behind it helps.
