We have figured out most of the things we have come across so far and we are new to owning our 1990 Komfort trailer. I have a couple of questions. I was told by the previous owner that he did not clean the fresh water tank, ever. I know this needs to be done but i need to know what the process is. Should i also be putting in an inline filter? I was also told that i should seal all the lights and windows with plumbers putty. It seems to me there must be a better way to do this. I have a small leak around the front window and need to fix it. I also notice a little moisture in the light covers after driving it in the rain. Any input you can provide would be great !!