Bluelab Guardian Monitor (Conductivity / Temperature / pH) Media but if pH is all

but if pH is all you need

no guessing what works with what

that dark-cycle drop is where a tube heater earns its place

so if the worst happens

and built to last longer than cheaper single-layer alternatives

Bluelab Guardian Monitor (Conductivity / Temperature / pH) Media but if pH is allBluelab Guardian Monitor (Conductivity Temperature pH) Complete Feeding, No Guesswork When growing hydroponically, it's essential to carefully monitor reservoirs to ensure that nutrients of the right strength, temperature and pH are delivered to your plants. The Bluelab Guardian is an all in one solution to monitoring every essential parameter. Should levels ever drop below, or rise above, pre determined values, then the easily programmed visual alarm