Good speech Maurice!
And as for the filters: I think, as Peter Finke says in the Paro Book, for beginners a filter is not wrong, for example concerning the mechanical job it does.
If you don’t have very clean tanks, means with leaves and alder cones and wood and if the nauplii for example didn’t sort out well from the cysts, a mechanical filter is a good thing to have even if the bacteria work is minimized..