pic 1

sump with reverse flow order to above, water enters from left

pic 2

one of the racks with skimmer, sump and top off vat in view

pic 3

another reverse order, this one sits next to the one in pic 1, the grey box is a modified "pro twin skimmer"

pic 4

The hydroponic nutrient "auto-pot" float valve, used for kalk

pic 5

the same rack as pic 2, different angle, with earlier design skimmer