Calcium Hardness

[pool512]

I have 2 questions on calcium hardness (CH):
1. When testing, you are looking for a change from red to blue. There is usually an initial change to blue, but with tiny red droplets still suspended in the water. Usually adding about 3 more drops will get the tiny droplets to disappear too. When do you stop counting?
2. PoolMath shows my CH out of range. Recommended is 250-650, and Ideal is 350-550. Depending on how I count (see #1) I am at either 230 or 260. I've previously been told here to not worry about CH of 250. This seems low to either range (recommended or ideal), and has been consistently low... should I be trying to raise CH? If so, what is a recommended product?

Thanks!

 

[Newdude]

We cover a wide range of folks. With low CH water and no rain, aim for 350 and it will stay there. With low fill water and lots of rain, aim for 450 and drift down to 350. With high fill water you can start at 250-300 and it will rise quickly.

When testing, you are looking for a change from red to blue. There is usually an initial change to blue, but with tiny red droplets still suspended in the water. Usually adding about 3 more drops will get the tiny droplets to disappear too. When do you stop

Do you have a speed stir? It's a game changer for calcium and salt.

Either way you want full change, add an extra drop to prove no further change, then subtract the last drop.

Calcium matters the least if you're 3 drops off. We'll know it's not 75 and not 800. 300 to 375 is mostly irrelevant

 

[wireform]

You count the drops that bring it to change to blue. The very last droplet that didn't cause a color change is deducted from the count and that's your final number. 250 -300 is perfect as you have hard water and eventually will be going up as you fill back for evaporation loss.

 

[pool512]

We cover a wide range of folks. With low CH water and no rain, aim for 350 and it will stay there. With low fill water and lots of rain, aim for 450 and drift down to 350. With high fill water you can start at 250-300 and it will rise quickly.


Do you have a speed stir? It's a game changer for calcium and salt.

Either way you want full change, add an extra drop to prove no further change, then subtract the last drop.

Calcium matters the least if you're 3 drops off. We'll know it's not 75 and not 800. 300 to 375 is mostly irrelevant

I've considered a speed stir, but this is a good reminder to order one.

We are:

low CH water and no rain

Given that, and that the CH has been consistent for awhile, it seems like a good idea to try to raise it to 350 from what you've said? Any recommendation on a product to use? Thanks again!