Best time; probably early evening, since chlorine added then will last all night. Also, filter needs to have been running about an hour before taking a sample and running about an hour after adding chemicals. But really, just do it regularly and keep notes on the results and what you add. I also note what my target levels are, since FC target changes as CYA changes and MA volumes to get to a given pH change as TA changes, for example.
SpeedStir; I don't think less lighting makes any difference. I think consistent lighting is most important so I take the samples inside to the laundry room where I have a sink and a countertop and do most tests there. That is away from the mosquitoes, comfortable in the winter, and near the computer so I can check the Pool Calculator for volumes to add. Also that is where I store my test kit.
True numbers; just know that you want to count all drops that change the colors. That means that when you think you are "clear" or "red" or "blue" add one more drop and be certain. Later on you will be able to know how red is "red". The SpeedStir helps quite a lot with that, but if you are not using that then hold the vial up to a white surface. Sometimes looking at it with a white cabinet or wall behind it shows the difference between "clear" and not quite clear.
Your numbers look OK in some areas, depending on what sort of pool surface you have. CH is probably low for plaster, OK for vinyl or fiberglass. For SWG pools your CYA needs to be higher so let us know what that addition of CYA ought to give you. Assuming that the target is between 60 and 80 then you are OK. Keep it near 7 or 8 until the CC goes down. I assume you might be trying to lower the TA with the pH a bit on the low side so if you aerate the pH can rise a bit. Not sure that is really important, depends on your pool surface I think.
You can add you pool info to your profile and it will show up on your posts. Very helpful for those who want to offer advice.
