FC much higher than TC

[George_]

I'm seeing an issue where my FC is much higher than my TC. PH levels are good and CYA is around 35. However, FC is around 10 and TC is around 2.
This was tested with 2 different brand of strips (I know...) and chemistry is not with BBB. Chlorine is typically added via 3" puck (calcium-based if I recall correctly) in the skimmer. Pool details are in sig. I'm trying to understand how FC can be higher than TC and what I should do about it.

 

[JohnT]

Can't be. FC+CC=TC, so FC will always be less than or equal to TC.

 

[George_]

Exactly what I thought with my, at this time, very limited knowledge.
Still both strips (different brands) showed the same thing.

 

[Easto]

I'm seeing an issue where my FC is much higher than my TC. PH levels are good and CYA is around 35. However, FC is around 10 and TC is around 2.
This was tested with 2 different brand of strips (I know...) and chemistry is not with BBB. Chlorine is typically added via 3" puck (calcium-based if I recall correctly) in the skimmer. Pool details are in sig. I'm trying to understand how FC can be higher than TC and what I should do about it.

How did you measure your FC and TC?

FC - Free Chlorine
CC - Combined Chlorine
TC - Total Chlorine

TC = FC + CC

Your TC will always be equal to FC (if you have no CC) or more than FC (if CC is present in the water)

 

[Beamup]

If the strips claim FC>TC, then they're not testing what they claim to be testing. Kind of like a calculator that claims 1+1=5 - if the tool gives a result which is wrong by definition, the fault is in the tool, not reality.

 

[frogabog]

Darn strips! puke (where's the puke emoticon anyway? lol)

 

[mynewpool]

Maybe your FC is 10 and your CC is 2 and TC is 12

 

[Butterfly]

Exactly what I thought with my, at this time, very limited knowledge.
Still both strips (different brands) showed the same thing.

Hi George, I'd say both strips are wrong. Strips are very inaccurate for testing your pool.

Do yourself a favor and get one of the recommended kits. See Test Kit comparison in Pool School.

In the interim, you could take a water sample to a pool store.

 

[George_]

I guess it's possible it should have been labeled CC and not TC on the chart. Other than that....I don't know.

 

[JohnT]

Darn strips! puke (where's the puke emoticon anyway? lol)

Here

 

[frogabog]

LMAO... that's a fast puke (and thick!)

I wanna puke that fast. Gotta remember to eat before I drink beer perhaps...