Second Water Test - AGP

[swanny297]

Hey Gang

I have been reading up on the BBB method and all the information on this site - I have a TF test kit on the way, in the mean time I have taken a sample to a local (reputable) pool store.

Saturation index - 0.4 (little high because pH is also high)
CYA - 86
TC - 2.3
FC - 2.3
pH - 8.1
TA - 150
TA adjusted - 124
Hardness - 78
Salt - 3100ppm

I was reading when using an SWG that if my CYA is 80, my target FC should be 6 - when I talked to my installer after the sample he recommended that I add about 1/3 gallon muriatic acid to lower the pH. Does my FC level need to go up and or my CYA come down?

I have approximately 17100 gallons in the pool, my SWG is on 100%, 24hrs/day - it is an Aqua Trol RJ unit.

Any input from you other BBB members to help me get started...

Thanks
Clint

 

[faby3003]

Can you describe how your water looks? Is it clear, cloudy, green, etc...?

For now, you should lower your pH to around 7.5 using muriatic acid. Use the pool calculator to calcalute how much to add (I get 38 oz.). Once you get your own test kit, you will want to lower your TA - follow this link on how to lower TA pool-school/lowering%20total%20alkalinity

You should use bleach to bring your FC up to 6. If you SWCG is not keeping up with your pools chlorine demand, you may have algae which is eating all your chlorine, or you may have something wrong with your SWCG.

 

[duraleigh]

Does my FC level need to go up and or my CYA come down?

Mostly, bring your FC up. I suggest you not trust the pool store result for CYA until your kit arrives. Post your own numbers and things may well change.

As posted above, lower your pH. The pool stores usually get that one pretty close to correct.

 

[swanny297]

Pool water is very clear - we have only been running everything for about a week now.

From what I have read in reducing TA, since my pH is also high, that muriatic acid will reduce both pH and TA, is that correct?

Both my SWG manual and the pool place recommend 1-3 for FC - should I be using more like 3-5 for FC as it shows in the pool school?

 

[Beamup]

Yes, MA reduces both pH and TA. But it reduces pH a lot more, so you generally use several pH cycles to bring the TA down appreciably. (Add acid to bring it down, TA brings it back up, repeat but the TA's a bit lower this time around.)

Industry recommendations don't take into account the effect of CYA on your FC effectiveness. This is why they're lower than Pool School calls for, and also why they're so prone to causing algae blooms.