FC decrease question??

[Rangerman]

Here are numbers from this morning:

FC 1.5
PH 7.8
TA 70
CYA 50


I'm getting an avg of 4ppm FC decrease each day, down from 5. There is no CC and the pool is sparkling with no visible signs of algae. I'm brushing about twice a week and the pool gets a very hot 8 hours of sun daily. There has been minimal use of the pool the last few days during this observation.
With the CYA at the high normal end of the TFP recommended scale, should I expect a 4ppm FC drop given the conditions outlined?

Thanks a lot everyone ... hope your summer is going great!

 

[reebok]

possible. you can try a cya of 60 to help some. I would try an overnight fc loss test just to make sure nothing's growing.

 

[JasonLion]

With a CYA of 50, I would expect FC to fall by 40% to 60% through a sunny day. If you started at 6.5 and fell to 1.5 then that is more of a drop than I would expect.