OCLT - is something living in my tub?

[treyragno]

I have been trying to SLAM my hot tub. It doesn’t seem to get up to SLAM level.

After adding chlorine I close the lid and wait several hours to check and add more chlorine.

I did an OCLT last night. I had 12ppm FC and 0.5 CC.

This morning I have 9.5 FC and 0.5 CC.

Do I have algae eating my chlorine?

Water is a tad cloudy/hazy and not crystal clear.

Any suggestions?

 

[Newdude]

After adding chlorine I close the lid and wait several hours to check and add more chlorine.

Hot tubs only take a few minutes to mix with as much circulation as they have. Like 2 mins instead of 15 for a pool.

Do I have algae eating my chlorine?

Have you been using it ? Residual organics hit hard after use. You are making people soup while enjoying it and all.

Any suggestions

Test/add to SLAM every hour and it should clear up pretty quick. Also, how old is the water ? At some point it gets away from you no matter what you do. 3-6 months for most, depending on usage and proper maintaining.

Have you ever purged with ahhsome ? That's another biggie on both new tubs and older ones. The come with stagnant test water in the pipes and then it only gets worse from there.

 

[Mdragger88]

There will always be some standby fc demand in a hot tub so doing an Overnight Chlorine Loss Test is a futile exercise & not a great indicator of a clean tub unless you already have a benchmark you can compare to.
You want to raise fc to slam level for your cya until it’s crystal clear & there’s .5 cc or less.
It’s unlikely to be algae, more likely bather waste as @Newdude refers to as people soup.
As he mentioned, retest & replenish slam level every hour or so. If it doesn’t clear after several rounds it’s probably time to purge, drain, refill & start fresh.
If you haven’t had any times that fc dropped below minimum for your cya there may be another cause for your cloudiness. (Fabric softener in suits, lotions, hair conditioner etc.) At any rate, cleaning filters & enough fc will cure it.

 

[phonedave]

Also, if you have a ozone generator in your tub, that will consume chlorine.