Here's an example of conflicting information. As far as what the calcium hardness reading should be: SwimUniversity says 175 to 275, poolcareguy-80 to 200, one CS person at our spa mfr-75 to 150 (for our acrylic spa), another one there- 175 to 225. a test strip container--250 to 450. Very frustrating!
What do you keep your calcium level at?
- Thread starter Sjde
- Start date
- Jun 22, 2014
- 52,086
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Yes, it can be frustrating. Of course all their levels are different for the other items as well. Many of them follow generic standard pool industry level recomendations and don't always take into account other factors such as shell type, location, temperature, calcium saturite index levels, etc. Here at TFP have have our Recommended Levels and use PoolMath to monitor those levels.
I am going to chime in and watch this one. I too have been told and have read many conflicting things about calcium hardness and total hardness. Including the post above which references the TFP "Recommended Levels" which are for pools and make no mention of acrylic spas or hot water. (Time to add a column for spas?)
One thing I that seems consistent is that an acrylic spa is not "sensitive" to calcium levels. Thus, as with vinyl pools, CH doesn't really matter, unless it's so high it's causing scaling issues.
My current strategy is to not worry about it in my acrylic spa. My CH tests at 70 with the Taylor kit; and "TH" looks higher than that on a "guess strip" at ~200.
I use a SWCG (Chlormaker) and the manufacturer recommends 200-300CH. They claim that the water is more corrosive at lower CH levels, with the 1500-2000ppm salt level. Based on that it seems it might simply be a good idea to have a "normal/traditional" amount of CH; however, there are some posts where venerable contributors (i.e. Chemgeek) state clearly that corrosion has nothing to do with low CH, and everything to do with low PH.
As I said I'll be watching the discussion. Cheers
One thing I that seems consistent is that an acrylic spa is not "sensitive" to calcium levels. Thus, as with vinyl pools, CH doesn't really matter, unless it's so high it's causing scaling issues.
My current strategy is to not worry about it in my acrylic spa. My CH tests at 70 with the Taylor kit; and "TH" looks higher than that on a "guess strip" at ~200.
I use a SWCG (Chlormaker) and the manufacturer recommends 200-300CH. They claim that the water is more corrosive at lower CH levels, with the 1500-2000ppm salt level. Based on that it seems it might simply be a good idea to have a "normal/traditional" amount of CH; however, there are some posts where venerable contributors (i.e. Chemgeek) state clearly that corrosion has nothing to do with low CH, and everything to do with low PH.
As I said I'll be watching the discussion. Cheers
The CH itself isnt corrosive, however its just small piece of the puzzle when it comes to the Calcite Saturation Index, a.k.a. CSI that Pat mentions.
If you use Pool Math you can play around with different chem levels on that app and you can see what happens to the CSI with different levels of CH, Salt, TA, pH, Water Temp and whatever else have you.
So yeah, its possible that there could be several or a wide range of CH that work for you, but it depends on other factors too...
If you use Pool Math you can play around with different chem levels on that app and you can see what happens to the CSI with different levels of CH, Salt, TA, pH, Water Temp and whatever else have you.
So yeah, its possible that there could be several or a wide range of CH that work for you, but it depends on other factors too...
when i ran a tiled hot tub i stayed around 250. worked good at that level. my inflatable tub i run around 175. our tap water is around 150-175. I've never had issues with foaming so i dont bother raising it at all. but none of my tubs have had warranty so im not concerned with that aspect.