When we got out '93 13' Scamp
last summer it was in need of much care. Several systems were in complete disrepair including the water-works.
The lines were completely filled w mildew and mold. The tank (original 10 gal) was much the same but there was no way to get inside to clean it.
So I ditched it all and opted for one of my own making. I have 2 4-gal tanks and ordered some great disconnects that are no drip when disconnected and offer a great flow rate when they are.
I can also take them out and use them table top with the original valve fittings.