can drain into the tank. in one of the back corners of the grow bed, drill a 1/2” hole for the tubing from the water pump to pass through.
place the water pump in the fish tank then set the grow bed on top of the tank. feed the tubing from the water pump through the 1/2” hole. leave enough tubing to extend about 3/4 the height of the grow bed and to loop around the inside of the grow bed. cut off any excess tube and fold the end over. seal the folded piece with electrical tape.
fill the grow bed with the growing medium to just under the top of 