New to TFP, but I've read the FAQ and will try to abide.
Pool water is clear and blue, but with googles/mask we noted some spots of algae spread throughout the pool, clustered in areas with least sunlight and probably lower water circulation. Determined black alage (smears green on white paper). Decided to attack with brushing and an elevated FC level.
In researching what level of FC was right for this situation here on TFP, I now think my first problem is a CYA problem. Current readings today with the Taylor kit:
CYA approx. 190 (no usable reading with straight pool water got 190 using 1/2 tap 1/2 pool water and doubling result as suggested in the Taylor book)
FC 11.8 (got a .4 on combined Cl)
Must I lower CYA before an algae treatment could even be effective?
Pool Math says to drain 58% of my pool - should I go that far?
Is high CYA not the most urgent problem relative to the algae spots?
Regular testing at pool store note CYA ">99" but this is never raised as a concern in need of treatment, why is that the case?
I use dichlor regularly as SWG just won't keep up (high bather load & open agricultural surroundings). From what I read on TFP that is likely the source of CYA as I do not add stabilizer ever. Obviously will stop now that I've found TFP, but need to know what to do to fix this now. As I said pool looks good, but the numbers might suggest a crisis and am looking for some advice.
pH 7.3 (prior to starting SLAM)