Pool-Dad....glad it's going well. Wish I could say the same. All of a sudden my pool is a disaster - looks more like milk than pool water. I think that, since it came on so quickly, it's due to the farmer doing major cutting in the fields on all sides of us. It went from nearly crystal clear to major accumulation of white water mold within 24 hours. So it's going to be a battle until they are done raking and bailing. Plus the bugs that came out of the fields are swarming around me all the time I'm working out there of late. Gotta say, there are times I could walk away from ALL of this - the pool, the big lawn, all the mowing, trimming, etc. and downsize into a nice 55+ community where I don't have to do any of the maintenance!!! It all ain't getting any easier. Good luck...hope yours stays clear for you. Don't be hesitant to use the Oxidizer. I looked back through my records and notice that last year generally every 4-5 days I added 2 quarts. Do you have any Ahhsome or the Aqua Finesse tablets? I truly think that with just the Bio-Guard products, etc. it wouldn't be enough - at least that was my experience over the years since the product called "Assist" was eliminated.
Regarding test kits - I use 2 Taylor kits: K-2006 and K-1725 (but only use the Peroxide side of the kit as explained previously). Then the other one I use is the LaMotte kit for Biguanide and pH (but only use that one for biguanide - it's ok but likely not as accurate as the 1725 would be IF I could get past the quotes issue that interferes with the color change.