Power metre buy one

as a novice i put in a lot of thought into my indoor system lights,water, fans etc all on timers & rails for lights but the one item that completed the system was the power meter that everything plugged into that circuit gave me a reading of exactly how many watts were being drawn eg my 1200w advertised led’s were only infact drawing 543w, this is an invaluable tool to calculate power usage, can be bought at any electronics store for bout $24, I have 4 leds on packaging amount to 3 600w & 1200w plus fans pumps etc meter only registers 1156w total