A lot of plaster in my vacuum

[MaverickFL]

I have a relatively small 12x20 9,000 gal pool. The pool was replastered almost exactly 2 years ago. I use a dolphin vacuum weekly and am seeing what seems to me like a significant amount of plaster in the vacuum each week. This week it measures over 1/3 of a cup. I don't know if this is normal or what could be going on here. THis is a QuartzScape finish. I am also having a lot of trouble balancing levels and I wonder if this could all be related ?

 

[wireform]

What makes you think it's plaster? How are you testing water?

 

[MaverickFL]

What makes you think it's plaster? How are you testing water?

Its hard to tell from the picture but If you look closely you can see the blue coloring fairly uniformly throughout. Testing water with Taylor 2006 kit

 

[MaverickFL]

I should add that I have a SWCG and a very large waterfall on the pool that I like to run all day and the pool requires a lot of acid to stay in the 7.6-7.8 range, about a gallon every two weeks. I add the acid directly to the deeper end of the pool but the pool is not very deep, only 5'-5.5'. Not sure if this could be contributing ?

 

[wireform]

Can you post all your pool chemistry please

 

[MaverickFL]

As of today:
FC: 5.5
PH: 7.6
TA: 100
CH: 360
CYA: 100
Borates: 60
Salt: 3900

 

[MaverickFL]

@wireform Any thoughts ?