guys i've taken all filters out, cleaned out backwards and forward with bleach, then rinsed fora few hours, installed all new filters and membrane, backwashed again for 2 and a half hours, now filtering for a few litres and still getting mid forties!!! which is the same as before new filters and membranes and clean out!!!! please help got to make water for monday. tds at the tap is around 420 which is typical for around here!