I gotta blanket!
But look at the advantages. I can live in the country in a small dwelling. I have a tractor in the Kitchen. A FMR TG500 engine in the lounge, and a den full of all sorts of interesting stuff, which would otherwise not be allowed. I can buy a fridge to replace the blown up one for £5, rather than buy a fashion statement. That is what the tractor is for, or other vehicle I feel like shoving in there. The cleaner cleans around them, does not moan, and gets paid £20. I can cook better than most women (not sure why they are supposed to be automatic cooks). Or I can go down the pub when I want. No campervan required. CASE SOLVED
Mind you a wife's caustic tongue might work wonders on a dirty fuel tank.
Shoving a magnet in the tank is a good idea as the iron in suspension as tiny bits will get removed along with the iron scrap, if used to scour the tank in some way. Indeed if I have a tank I suspect is a bit contaminated, but I am not going to clean it, I put a polymer magnet on the end furthest from the tap, so as to pull the magnetic crude out of suspension and away from the tap. Using sand or gravel introduces a non metallic substance to the frey which is not as easy to control, or remove. I have even had tanks with trapped stones in, complete with cornering noises as the damned thing rolls round the tank.
Anyway our adviser feels his method requires no additions to effect a clean inner tank. I just wonder if it will not find out weak tanks with rust spots, as you get on a Treinkel, for instance. Not that this is a reason not to clean and find out before a fire, but many is the tank I have cleaned to find it is holed on removing the crud. So that bucket of water needs to be handy, for the corrosive solutions will surely find those weak areas and make their escape, if they can. Also some tanks have the fuel tap threads brazed on. This will be attacked more vigorously than steel. Be aware of that possibility.