the pump is perfectly watertight (tested). It does need a little cleaning but it is just dust, no rust anywhere important. 8400l/h, 10m head....can't wait to have it running

How much would you say an aluminium radiator looses against a copper one performance wise?

P.s. you are absolutely certain that you don't have any corrosio going on in your system?

How much would you say I would loose by using antifreeze in terms of performance?