Calcium deposits?

lsurefugee

Gold Supporter
Jun 21, 2023
42
Baton Rouge, LA
Pool Size
15000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
I need some help figuring this out. We have a spa/pool combo. Recently, the seats in the spa started to form “crystals”. The surface of the pool steps do not have this problem, only the spa portion. I usually only run the spa portion once weekly for about 30 min, unless we decide to get in it. I’ve used some wet/dry sandpaper and it seems to easily take off these “crystals”. I have suspicion that this is mostly like calcium? I struggle with keeping pH < 7.6. I usually hover at about 7.8 with TA around 70-80. If I sand these spots down, they are usually back by the next day. Any additional thoughts would be helpful.
 
I need some help figuring this out. We have a spa/pool combo. Recently, the seats in the spa started to form “crystals”. The surface of the pool steps do not have this problem, only the spa portion. I usually only run the spa portion once weekly for about 30 min, unless we decide to get in it. I’ve used some wet/dry sandpaper and it seems to easily take off these “crystals”. I have suspicion that this is mostly like calcium? I struggle with keeping pH < 7.6. I usually hover at about 7.8 with TA around 70-80. If I sand these spots down, they are usually back by the next day. Any additional thoughts would be helpful.
Check your calcium levels. This spring I have deposits on the walls also. I checked the levels and it was way low. I have already added 15lbs and still it hasn't gotten to the middle of the recommended range. Lots of rain over the winter months likely depleted your calcium level.
On a side note. Your city water may contain a bit of calcium but it is not enough. I checked mine yesterday and it is only about 100ppm. That was direct from water spigot. Once it hit the pool it likely is much less.
 
I found this article and this appears to be happening to our pool. We live in South LA but did have a temperature of 9* this winter. It did stay below freezing for about 48-72 hours.

 
I found this article and this appears to be happening to our pool. We live in South LA but did have a temperature of 9* this winter. It did stay below freezing for about 48-72 hours.

The Borate Pool Opening in Aqua Magazine discusses how borates can limit pH rise while a pool is closed for the winter. High pH while a pool is closed can cause scaling. Those that find their pools with very high pH at Spring opening may benefit from borates, with the pool open or closed