Hello and welcome to the forum! 
Those are some interesting circular spots. Any UFOs in the area? 
Okay, let's start with the following:
1 - Update your signature with all of your pool and equipment info (see mine as an example). Appears to be plaster, but all info will help.
2 - How do you test your water?
3 - Can you post a full set of water results? (From TF-100 or Taylor K-2006)
4 - How do you chlorinate?
5 - Pool history? New, or existing home purchase? Anything else?
6 - Any autmoated cleaners used?
That should help us get started.
Those are some interesting circular spots. Any UFOs in the area? Okay, let's start with the following:1 - Update your signature with all of your pool and equipment info (see mine as an example). Appears to be plaster, but all info will help.
2 - How do you test your water?
3 - Can you post a full set of water results? (From TF-100 or Taylor K-2006)
4 - How do you chlorinate?
5 - Pool history? New, or existing home purchase? Anything else?
6 - Any autmoated cleaners used?
That should help us get started.
I use the TF-100 Pool test kit.
it is a Chlorine pool.
It was an existing pool with home purchase
I use a suction side cleaner We named him Flash after the Sloth in Zootopia
i will be testing the water this afternoon.
it is a Chlorine pool.
It was an existing pool with home purchase
I use a suction side cleaner We named him Flash after the Sloth in Zootopia
i will be testing the water this afternoon.
Spots of that particular pattern are not reminescent of typical organic or metal staining unless something round like that rested on the floor's surface for a while. I don't see how the cleaner could contribute to those. I have suspicions about the base underneath. Your water tests later might help. I'll ping the assistance of others to see what they think. @JamesW
Are the spots new or old? Were the spots in the pool when you bought the house or did they recently appear?
I am not sure what the previous owners did. We have not we put them in the floating dispenser
The spots are too perfect to be a chemistry issue.
I suspect that someone probably threw tabs in the pool.
I suspect that it probably wasn't the previous homeowner, but someone responsible for the house between owners.
Was the house unoccupied for a while?
I suspect that someone probably threw tabs in the pool.
I suspect that it probably wasn't the previous homeowner, but someone responsible for the house between owners.
Was the house unoccupied for a while?
I think the light colored cloud shapes are clouds... I think that’s just the reflection of the sky in the water.
