I'd love to. 2 things make you lose FC. The UV from the sun (daily burn off) and organics (algae, residual bather waste, etc).can u explain to me in layman's terms exactly what this overnight chlorine loss test is
If you lose FC overnight, with no sun, then algae is brewing. (And will be why the water is getting funky).
So to run the overnight test :
1) test FC after dark
2) test FC at sunrise. (Just before).
*both tests need to be good and mixed first. Leaving the pump on overnight will let you sleep until the last second.