I thought something was missing from the end of the pick up pie and now I know it was a filter. I presume it was removed because it kept getting blocked. I will measure the pickup pipe now out of interest as to where it will come in the tank. I am fitting a electric pump and inline filters so will not put one back in the tank. The breather pipe on top of my tank did have a couple of minor rust holes at the end but I have fixed them now.