Is an indoor pool considered the same as an outdoor pool as far as the
CYA/FC chart is concerned?
CYA/FC chart is concerned?
CYA/FC chart for indoor pool
- Thread starter Water_man
- Start date
I'm sure someone will correct me if I am wrong, but Yes. The relationship has nothing to do with sun or lack of sun.
However, with an indoor pool, you don't need NEARLY the levels of CYA as you would in an outdoor pool with full sun all day long! I don't remember the exact recommendation, I believe but it was around 20-30ppm.
However, with an indoor pool, you don't need NEARLY the levels of CYA as you would in an outdoor pool with full sun all day long! I don't remember the exact recommendation, I believe but it was around 20-30ppm.
The Mermaid Queen has it right. The CYA/Chlorine relationship holds in any case. In an indoor pool we recommend CYA be between 20 and 30, and the more common practice is to have CYA at zero. When CYA is between 20 and 30, things behave much as you would expect given experience with an outdoor pool. But when CYA is at zero, things behave a little differently.
The main issue, is that when CYA is zero, a FC level of well below 0.5 is sufficient to kill algae, but gets used up way too quickly to maintain reliable sanitation. Therefore indoor pools, without any CYA, are actually routinely run above shock level, sometimes way above, so that the FC doesn't all get used up at the first sign of contamination. That leads to some additional complications, such as fading and wearing out bathing suits fairly quickly, that are never normally an issue in an outdoor pool.
The main issue, is that when CYA is zero, a FC level of well below 0.5 is sufficient to kill algae, but gets used up way too quickly to maintain reliable sanitation. Therefore indoor pools, without any CYA, are actually routinely run above shock level, sometimes way above, so that the FC doesn't all get used up at the first sign of contamination. That leads to some additional complications, such as fading and wearing out bathing suits fairly quickly, that are never normally an issue in an outdoor pool.
