The garden pump had a LED ring light around it with a separate transformer supplying 14V AC which passed through a LDR switch then onto the LED ring. While I can find very simple 230V triac based circuits I'm struggling to find one for such low AC voltages. I have attached an example of such a 230V AC. Can I modify this to work...my calculations suggested that a 1n4001 diode and a 270K pot would be OK. Any thoughts greatly appreciated. Julian