OK,
That's better.

I'm not the metal expert but I THINK an iron level of .5 isn't a problem. MBar knows better.

CYA takes DAYS to dissolve, and the older it is, the longer it takes! You may be a week before you get a good reading.

You STILL need to follow Mbar's advice and get your FC up to shock level (at least 10ppm) and keep it there to fight what you are growing. I would go as high as 15ppm because when your CYA begins to show, that will be the shock level. She said increase it slowly, and I would do so.

Please go back and re-read her post. I think it's still what you need with my few comments added.

Marie, if you could confirm my advice......Thanks!