Holding tank issues

I purchased my Class A RV used. It was a monument to neglect and abuse. The previous owner cooked with grease and oil a lot and apparently dumped most of it down the drain. Shortly after I purchased the rig my grey water tank clogged and I restarted it by shoving a hose up the drain. A few weeks later I noticed the tank was leaking. Further inspection found an 18" crack that had been sealed with waste grease that had collected in the tank bottom. Unfortunately, when the drain had clogged earlier the weight of the water in the tank reopened the crack. It wasn't immediately apparent because the tank had an insulated shell surrounding it where it extended into a storage bay. I ended up replacing the tank, to the tune of about $550 for a new tank, plumbing parts, and spray-on insulation for the section of the tank located outside of the storage bay. It's taking a while but I'm slowly making my rig right. None of the problems I've encountered kept me from taking my 5,400 mile Grand Western North America Tour and Shakedown Journey last year.