ok ty guys, 26,000 gallon plaster pool 17 yrs old, cartridge filter (4 tall ones), 3/4 horse pump, solar, heater, spa (connected w/ spillover to pool), secondary pump for cleaner.
I use liquid chlorine (sodium hydrochlorite 10%), when I had zero cya the store wanted me to use 3 gallons of the liquid so I will put in the one gallon I have with the 1/2 lb of dry and see where I am. I will probably not try to lower the alkalinity unless I see that it is rising. I thought that you might say that about the phosphates, actually I was hoping...it is good to have you confirm that. I do not think it is pollen, I have nothing around the top, and it looks just like yellow algae, which I am very experienced at growing...LOL It has only happened twice and i brush it and it is gone, it happens on the afternoon sunny side of the pool.