Description
The smaller (inlet) fitting is used to pump nutrient into the tray (flooding), while the larger (outlet) fitting with the extension sits higher in the tray.
Once the nutrient level in the tray reaches the height of the outlet screen, the excess nutrient can drain back to a reservoir.
The extention can be adjusted for more height, and extra extentions can be added for a deeper tray.
The tub outlets supplied with these fittings have a 13mm barb (smaller one) and a 19mm barb on the larger one.