Inline Frog chlorine cartridge efficiency?

[norcalhottub]

I have a 375 gallon Caldera Vanto using the Frog inline Mineral/Chlorine system.  It almost seems like the chlorine levels cannot maintain the desired levels per the test strips after say 2 weeks.  Advertised recommended usage is 1 month however it seems I am only getting half that.  The spa is used by 2-3 person family maybe 2-4 times per week. I have both cartridges set to 3 and 3 while F1 and F2 settings to 1.5/1hr.  Should i try to increase chlorine cartridge setting to 4?  Currently I am supplementing with Spa 56 to maintain chlorine but would like to see the cartridge do it's job a bit more. 

[castletonia]

The blue mineral cartridge needs to be set at 6.  I would probably bump the chlorine cartridge up to 4.  Assuming your pH and alkalinity are balanced, I would get your water tested for phosphates.  High phosphates will consume chlorine quickly.  I personally would up your filter settings a bit to at least 4 hours daily.

[norcalhottub]

Thanks for the info.

Completely missed the mineral settings there. Thanks I’ll make the adjustment!

I believe the 1.5/1hr filter setting is x2 each making it a total of 5hrs a day? Or am I understanding this incorrectly.

Yes my pH and alkalinity are within range for the most part but chlorine mostly seems to go low. I’ll go ahead and make the adjustments and see where it goes from there. Thanks again!

[Sam]

Are you using the specific frog test strips?  The free chlorine level is really low and wont show up on a lot of strips.  I also find that really heavy bather loads require supplemental dichlor.  The @ease system is great but not for heavy bather loads. 

[norcalhottub]

For kicks I've tried both the Frog @ease and Frog test strips simultaneously and have gotten the same results.  The chlorine level is definitely not darker than suggested as well as reads 0ppm. I agree, i've had a couple of run-ins w/ musty-green water after some heavy usage in the beginning, that prompted me to supplement w/ the Spa 56 granules.