New convert to BBB just lowered CYA & starting fresh

Jump to latest Follow Reply
M

mjdowd

0
Jul 9, 2010
3
charlotte, nc
We went through a couple of partial drains & refills over the last 24 hrs & have succeeded in lowering our CYA to 44. YAY! We have not yet added any chemicals & have completely removed all tri-chlor pucks from the auto feed and skimmer baskets. Here are my current numbers:

CYA 44
FC 0
CC .2
TA 80
CH (don't know because I ran out of reagent in my K-2006)
ph 7.4

What balancing (if any) do I need to do? Based on reading the forums, I think my targets for TA, ph & CH may have changed from pool store recommendations. What are my targets?

I KNOW THAT I HAVE TO ADD BLEACH TO RAISE FC, but thought I should do that tonight & raise to shock level...esp. since the problem that caused me to convert to BBB & do all the draining to lower CYA was because I couldn't maintain FC over .2 no matter how much chlorine I added. Is that the right approach?

We would really love to swim. We have had weeks of really high temps & bright sunlight on the pool all day. Is it realistic to hope that we can swim tomorrow if we shock successfully tonight?
Thanks for your help!!!
 
1. visit pool school link

2. Locate the FC/CYA chart to see your target level of FC for a CYA of 40ish.

3. Use the pool calculator to calculate how much bleach to add to raise your FC to the target level given your pool volume.

No need to shock unless you suspect algae. You couldn't maintain FC because your CYA level was so high that the chlorine was bound (and not free).
 
D'ONT WAIT! Everything is good to go but the chlorine. Don't shock yet! CC indicates no need to. Get about 6 ppm based on your cya level and gallons. Looks like 261 ounces to start--- a little extra won't hurt.. Pour slowly in front of a return 2 minutes per gallon. Let the pump run 3 or 4 hours at least. GET some chlorine in there and swim! (after an hour or so anyway). Quit reading and go get some bleach as soon as you calculate how much you need! Grab 3 or 4 extra gallons to boot while you're at it. Enjoy, and welcome.
 
Yeah, your other numbers look good.
If the water is clear, you don't need to hold off swimming. That being said, you should add enough bleach to reach your target, wait 30-60 mins and verify your FC is there, add more bleach if necessary, repeat testing procedure until the FC is holding at your target level. Then tonight do an overnight FC loss test. If the FC holds overnight, you don't need to shock. But I wouldn't swim until your FC is in the recommended range. :)
 
I would put 3-5ppm FC in the pool via bleach and swim immediately. Once you have the FC in the pool, the pool is balanced and ready to go. Check FC again after you swim to see how much is left and calculate a dose big enough to bring it back up to 5ppm FC.
 
Thank you all for your replies! I added bleach yesterday afternoon to raise FC to 6ppm (with CC .2ppm) and we swam last evening. It was lovely!

I did the FC loss test last night. At 8pm, FC was 5.8 with CC .2. At 8am this morning, I got FC 4.2 and CC 0. I was a little bummed that the FC loss was greater than 1ppm. Is my loss of 1.6 a concern? But I was psyched that the CC went to 0. I added enough bleach to raise FC back to 6ppm this am & will see how it holds through the day. My current CYA is about 35.

I read Pool School and got the target ranges for TA, CH, pH, etc. But I'm a little confused by what MY specific targets are and the impact of the spillover spa, waterfall & dark plaster. My pool store gave me a target of 120-150 on TA, the Taylor test kit book has a target of 80-120, and I got used to aiming for about 120 because the tri-chlor pucks seemed to lower it pretty regularly. So, do I aim for 70-90 or 60-80? Pool School says
Pools with plaster surfaces should factor their CSI into the preferred TA level decision.
Click to expand...
Not sure what that means. For CH, I was always aiming for about 200 for fear of scale and having to drain if it got too high, but Pool School recommends 250-350 for plaster. And I read in Pool School that
Aeration will tend to cause the pH to rise. This can be mitigated by lowering TA
Click to expand...
So, I'm thinking that my new targets are: TA 60-80, CH 250-350 and ph on the lower side of the 7.2-7.8 range (ideally about 7.4) Does that sound right?

Thank you again! I really appreciate your replies.
 
An overnight loss of 1.6 is a cause for concern. Given everything that is going on, I wouldn't worry about it too much unless it does that again tonight. For now, just raise the FC level a little higher than you otherwise would and hope that it goes away tonight.

If you follow the recommended levels chart at Pool School you don't need to worry about CSI at all.
 
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply