I do the same thing at the end of every trip.
I just tried Unique Digest-It Tank Sensor Cleaner a couple months ago. This stuff is amazing. I really thought my tanks were clean, but couldn't seem to get rid of that last 1/3 light and read empty no matter what I did. Give it a try, it really works!
https://www.amazon.com/dp/B0741NL8S5...v_ov_lig_dp_it