The irrigation of cions in flood tables provides an equal supply of water for every single plant. The water floods the table, feeds the plants and then drains slowly and steadily.
While draining, small pieces of plants or dirt can reach the drain-hole, this can cause a blockage. To avoid this, you need a prefilter. You attach the prefilter to the drain-hole by screwing it to a reducing spout as a counterpart. The other end of the spout allows to attach a hose connector with a 1.9cm (3/4 inch) thread for a 20er hose.
All three needes parts are included in this drain-kit:
So, first: drill a hole (please use a hole cutter, normal drilling can destroy the plastic. - If you don't have a hole cutter, we can drill it for you by charging only 3,- Euro for the work.)
Second: prefilter into the inside of the flood table, holding up the reducing spout.
Third: screwing the 1.9cm (3/4 inch) thread of the hose connector into the reducing spout, attaching the hose to it.

The drain-kit contains:
1 x prefilter
1 x reducing spout
1 x hose connector

You should use a thread seal tape to seal the thread waterproofed.