I recently resurfaced my pool with a Pebble-Tec mini pebble finish. Pebble-Tec recommends maintaining the following levels:
FC: 1.0-3.0
pH: 7.2-7.6
TA: 70-100
CH: 150-300
CYA: 20-30
CSI: -0.3-0.3
TBF/Poolmath have different recommendations. FC and CYA are fine, the differences are understandable based on the interaction of CYA with the efficiency of chlorine. But I don't really understand why the TBF/Poolmath recommendations are so different for other chemistry measurements. For example, TBF recommends an ideal range for pH of 7.6-7.8, which is above the Pebble-Tec recommended level. TBF has an ideal range for TA, 60-80, that has a low end below the Pebble-Tec recommended level. CH is way off the charts, with TBF recommending an ideal level of 350-550, far higher than Pebble-Tec's recommended level. TBF's take on CSI is understandable, since I think the concensus there is still to keep it in the -0.3-0.3 range when possible, but don't freak out if it goes as low as -0.6 or as high as 0.6 for relatively short periods of time. It is bothersome to me, however, that CSI is downplayed in a sense, emphasizing maintenance of the other parameters. It seems to me that CSI is the primary indicator of water chemistry balance, so as long as other parameters are maintained within measureable levels, CSI should be your holy grail.
So I guess I really have two questions:
1. Does Pebble-Tec have inside information on how their product needs to be maintained, or are they just blindly recommending levels that have been out there for decades?
2. When it comes to CSI, why wouldn't it be the primary parameter? Why worry about maintaining strict ranges on other parameters, as long as CSI is between -0.3 and +0.3?
Thanks in advance for your help in understanding water chemistry.
FC: 1.0-3.0
pH: 7.2-7.6
TA: 70-100
CH: 150-300
CYA: 20-30
CSI: -0.3-0.3
TBF/Poolmath have different recommendations. FC and CYA are fine, the differences are understandable based on the interaction of CYA with the efficiency of chlorine. But I don't really understand why the TBF/Poolmath recommendations are so different for other chemistry measurements. For example, TBF recommends an ideal range for pH of 7.6-7.8, which is above the Pebble-Tec recommended level. TBF has an ideal range for TA, 60-80, that has a low end below the Pebble-Tec recommended level. CH is way off the charts, with TBF recommending an ideal level of 350-550, far higher than Pebble-Tec's recommended level. TBF's take on CSI is understandable, since I think the concensus there is still to keep it in the -0.3-0.3 range when possible, but don't freak out if it goes as low as -0.6 or as high as 0.6 for relatively short periods of time. It is bothersome to me, however, that CSI is downplayed in a sense, emphasizing maintenance of the other parameters. It seems to me that CSI is the primary indicator of water chemistry balance, so as long as other parameters are maintained within measureable levels, CSI should be your holy grail.
So I guess I really have two questions:
1. Does Pebble-Tec have inside information on how their product needs to be maintained, or are they just blindly recommending levels that have been out there for decades?
2. When it comes to CSI, why wouldn't it be the primary parameter? Why worry about maintaining strict ranges on other parameters, as long as CSI is between -0.3 and +0.3?
Thanks in advance for your help in understanding water chemistry.