CYA calculation....

[gtnos]

so, getting excited. We are going this week to order pool (Desert Spring 16x32 with deep end) and PB said he should be able to get us up and running towards end of May. Says 3 days from dirt to pool!

he has a transfer pump and we will of course transfer 6400 gallons of perfectly balanced pool water from our current pool.

my CYA level is 50 in this pool (im keeping on the high side due to direct sunlight all day long).

Being that the new pool is ~20000 gallons (its hard to calculate an ABG pool with 7 ft deep end, without its 17800, so im thinking around 20000 with deep end)

soon as he transfers the water over and we start filling up, im dropping in a "stabilizer sock" to start getting CYA up ASAP

can I assume an initial CYA of ~16 since my intex pool water will be diluted down 2/3rds? (6400 x 3 = 19200)

i will of course test my CYA one last time in my good 'ol intex before it gets transferred to verify its still at 50....

 

[jblizzle]

That would be about right. I would add about 20-30ppm more and then retest in a week and adjust again if needed.

 

[mac4lyfe]

Sounds like a good plan. Your calculation is sound. I'd try to put that sock right in front of the transfer pump so that it can help dissolve the stabilizer quicker.

 

[Isaac-1]

You might even want to start a few days early and bring your current pool CYA up to the 80 to 100 ppm range, just raise your FC accordingly and stay on top of it. The real danger with a CYA of 80+ is not an issue of getting algae if you maintain FC, but instead it is of defeating algae if your FC ever drops too low, whether through neglect or weather events, etc. As well as testing accuracy issues when CYA gets high to accurately know what your goal FC should be. Both of these are fairly mood with a measured addition, a few days before the water transfer / dilution.

Ike

 

[gtnos]

You might even want to start a few days early and bring your current pool CYA up to the 80 to 100 ppm range, just raise your FC accordingly and stay on top of it. The real danger with a CYA of 80+ is not an issue of getting algae if you maintain FC, but instead it is of defeating algae if your FC ever drops too low, whether through neglect or weather events, etc. As well as testing accuracy issues when CYA gets high to accurately know what your goal FC should be. Both of these are fairly mood with a measured addition, a few days before the water transfer / dilution.

Ike

i thought about that, bringing it up to about 120 before its transferred.... that would put it at 40 ppm diluted.

can I get some additional weigh in on this? my thought is:

1. Instant CYA level without having to wait for granules to dissolve?

cons to this? (other than 1 week of increased chlorine usage in the intex)

 

[jblizzle]

While the FC level will be higher in the Intex, the actual FC loss should be less with the higher CYA. I see no problem with this.

 

[gtnos]

well then, thats what ill do. about 5 days prior to start of build, ill bring CYA up to 120 in the intex along with the proper chlorine addition (93 oz by pool calc) so that I have will have instant CYA on the fill up of the new pool.

man I love this site...... Thanks jblizzle!