Here's a picture from November last year. This was the worst section of the spa.

Here's a picture taken this morning. I might have to retake it later, when the light is better.


It's not completely eradicated, but the pool has been swimmable the whole time (aside from water temperature).

Looks like you're making really good progress! Thanks for documenting it; it goes to prove that you really can get rid of it, with a little diligence and a lot of patience.

I have a similar lookinzg scaling issue from my pre-TFP days. What has your method been to get rid of the scaling? I have been maintaining the csi in the 0 to -.3 range for a month but have not noticed any improvement. I'm hesitant to do any sort of acid wash. Scrubbing with a nylon brush seems to have no effect. Should i try a wire brush?
Thanks!!

Maintaining negative CSI, wire brush, and time. The big change in appearance started after the winter rains, when I diverted a downspout to the pool and replaced over half the water in about a month's time. There's no Calcium in rainwater!

There has been little to no rain here but i have bben planning to drain some water and let rain fill the pool as soon as i can. My fill water has a high CH so that's not an option. I plan on draining partially for winter soon Which should help a lot! We got huge snowfalls here last year so my fngers are crossed!

A month is nothing, as far as this process is concerned! It took about a year for me to remove less scale than Richard had; I actually didn't do a whole lot of brushing but just let the water work on it. Below is how mine looked originally; I don't have an 'after' picture, but just imagine the white coating gone.

Another update. I guess I should have checked what I took pictures of last time, this shot is to the right of the others, but you may be able to spot the matching uneven tiles.

Wow what a difference.

Good job Richard!

No pictures this time - there's no room in the pool to empty the spa water into. I added about 3" of rainwater this last "storm." But anyway...

Last full set of tests was 2 weeks ago. CH was 700. Somewhere I figured out that the average pool depth would be 60". So...3" dilution in 60" water should be 5%. So maybe, just maybe, I'd be able to detect CH dropped. I was looking for 675 today. Instead, I have 725. Which means: I'm still stripping scale!! That Calcium had to come from somewhere.

I'm so tempted to go berzerk and run the pH down in the sixes to accelerate the process, but I have no desire to buy a new heater. So slow and steady we go, pH about 7.2, CSI hovers around -.5 > -.6.

Another rain shower last night. They never gave expected rainfall amounts, so I figured it would be minimal. But this morning the pool and spa were at the same level. Roughly 5% dilution. Now I wish I'd drained it down a little. I'm pumping it out from the main drain, but I know some of that precious Calcium-free water is sneaking out.