fc-low as I have been waitnhg 28 days before I can add salt due to new plaster. Been using liquid chlorine.
As stated earlier I feel it might be the metals coming out as I was filling the pool for three days and adding sequestrant in that time. Thanks for all the help
It's still a guess, but I would lean towards dead algae as the cause. High temps and low chlorine for 30 days allows algae to get started. YOur low doses of FC are killing some of it but not all. What is killed, gets caught up in the filter and is (for me, at least) normally a brownish-yellowish color.
If you have sequestrant in the pool, that would tend to keep the metal in suspension and not precipitate in your filter.
You're not on a well but you're adding sequestrant, why?
Since you're on public water you can get an assay (water quality report) and find out if there is any metals in your fill water. A lot of places even have them online now. I'd suggest getting one because if there are no metals then sequestrant is a waste of time and money. Also, you putting stuff in your pool that you don't need.
You need to raise your FC up too. I, like Dave, suspect algae. How are you testing?