First off, I am not new to pool maintenance. Kept two Intex pools sparkling and balanced, and this will be my 4th summer on a 24 x 52 AGP round REAL pool lol. After uncovering a month ago, I had the usual dirty water. It sat uncovered a month or so at about 2/3 full, so green algae took hold. Yesterday, I dumped 7 pounds CYA in a pillow case, tied it around a hose, and topped off the pool with the remaining 1/3 of its capacity. By the time it was full, the CYA had dissolved, as the pillow case was empty (no it wasn't ripped). I did not test for FAC, since the pool had sat idle all winter, and then uncovered and in the sun for the last month prior to top-off. I super-chlorinated last eve to 30 ppm with 12% liquid Sodium Hypo, as I do every spring for the last several years. 1.5 Hayward LX Pump and 175 Lb Hayward sand filter ran all night. This morning, no evidence of green. But of course water is cloudy and can barely see the bottom. I can clear that up with some Baquacil Floc, following the filter-aide directions, again, as I do every year. This is where it gets strange. This morning, I collected a water sample and sat down at the kitchen table with my Taylor K-2006 kit, which uses FAS-DPD. My FAC test showed 30 ppm. Brand new reagents and DPD powder this year. This truly baffled me, as all the other years, that 30 ppm super shock decreased to less then 5 ppm by morning. Ph showed to be 7.4 or thereabout (ph can be difficult to pinpoint with a comparator, but my sample did not have that wild purple color that would clearly show a way high ph). Just for kicks, I put in a drop of acid demand reagent...No change. Then another...and another... 12 DROPS LATER, I saw the first visible color shift showing a now corrected reading of 7.2. This normally happens with just one or two drops. I then moved on to TA and found a reading of 125 (raw, not taking into account cyanurate correction). Strangely, my TA color shift went from green to an endpoint of a funky orangeish color instead of the usual red. My CYA test was 70 -- I know a bit high, but I usually start the season around there, as we can get a lot of rain here, plus more backwashing during pool start-up etc, so by mid summer, my CYA is typically centered within the 30-50 range. My question...can a high chlorine level of 30 ppm cause such screwy things in the other tests? I know that very high chlorine can 'bleach' out reagents, but face it, 30 ppm is exorbitantly high. Also, how in the heck can a green pool maintain a 30 ppm super shock? CYA doesn't protect chlorine from depletion from a high-demand 'task', but rather from breakdown/"evaporation" due to sunlight. Any thought? Anyone? Bueller?