Is a loss of 5ppm a bad sign or does it mean I'm pretty close to winning the battle?
Yes trust your results.
Great, sounds like I've been doing that right. When testing my FC and it goes clear after one drop, if I then leave the sample while I attend the pool...Come back and it's a little pink...is this normal or mean I'm not measuring FC properly?
Perfectly normal...is this normal or mean I'm not measuring FC properly?