Conversion: Bleach Gal. to SWCG Lbs. of Chlorine??

[catnip]

Does someone have a handy conversion from Bleach Gallons (6% or otherwise) to SWCG pounds of Chlorine? I'd like to use this information to help size a SWCG by equating it to the the output of BleachCalc. In other words if in my case 3 gallons of bleach is required raise FC by 10 ppm, I'd like to know how may pounds of Chlorine the SWCG will need to generate to raise FC by 10 ppm.

The SWCG companies market their products based on maximum pool size, but I've noticed the maximum pool size vs. lbs. of chlorine generated is not linear. So, I would like to do my own own calculations based on what I know works with bleach on my pool vs. the chlorine generation capacities of the SWCG's. Make sense?

[mas985]

1 lbs of chlorine is approximately equal to 1 gallon of 12.5% bleach or 2 gallons of 6% bleach. So for 3 gallons of 6% bleach, you would need about 1.5 lbs of chlorine. Most SWGs generate less then that even running 24/7.

By raising your chlorine by 10 ppm are you attempting to shock with your SWG? I would not recommend using the SWG to shock but to continue using bleach.

[catnip]

Mark, thanks. That's an easy conversion to work with.

Part of the reason I wanted to this information is to see if a SWCG would have the capacity to administer a shock dosage of Cl. The Pool Pilot line claims to have Cl capacities of 1.28, 1.56 and 1.92 lbs. of Cl per day. My reason for considering this is that I have to depend on a pool service company for maintenance for three weeks out of every four, and they currently use Cal-Hypo for shock...which I would prefer to avoid.

Is there a particular reason, other than extra wear and tear on the cell and the time required to build up to a shock dosage that I should avoid using the SWCG to shock the pool?

[mas985]

Is there a particular reason, other than extra wear and tear on the cell and the time required to build up to a shock dosage that I should avoid using the SWCG to shock the pool?

You covered most of the reasons but you should rarely need to shock the pool at all anyway and if you do, then try to get the pool service to use bleach. After all you are paying for it.

[Poolsean]

"Part of the reason I wanted to this information is to see if a SWCG would have the capacity to administer a shock dosage of Cl. The Pool Pilot line claims to have Cl capacities of 1.28, 1.56 and 1.92 lbs. of Cl per day."

Every manufacturers capacity claims are rated for maximum output setting @ 24hr/day, with ideal salt levels. Yes, it will produce those figures. I was tested and verified by NSF.

"My reason for considering this is that I have to depend on a pool service company for maintenance for three weeks out of every four, and they currently use Cal-Hypo for shock...which I would prefer to avoid."

The need to shock by a pool service company is because most pool service come once a week, so they are only dosing your pool weekly. This in itself is shocking the pool, but as an extra preventative, they may do an additional shock dose. What happens to your chlorine level after 3-4 days is that it starts to drop pretty low. This gives the algae a chance to start, but also allows the germs to be more active (read...not safe).
Remember that with swg, the very process of generating chlorine is shocking the water of the combined chlorines (chloramines), thus the need to periodically shock the water is virtually eliminated. Just about the only times you will need to shock is for inclimate weather conditions, or large pool parties. As as has been suggested over and over again, manually shock using liquid or cal hypo (so long as you're not already dealing with high calcium hardness levels). This will help extend the cell life.

[catnip]

Sean, I have picked up the general consensus that SWCG pools seem to require shock dosages less often than traditional Cl maintenance methods. I'm certainly not stuck on using the generator for shock dosages; just wanted to understand if it's feasible. I think I understand your answer is "yes", but that manual application of liquid Cl or perhaps Cal-Hypo is preferred.

I should also clarify that the pool service company uses Tri-Chlor pucks in an in-line chlorinator plus shocks with Cal-Hypo. Sometimes we get through a week with good chlorine levels and others time not, which I believe is the basis of the algae problem (mustard and black BTW). Plus we have the negatives introduced by Tri-Chlor, and Cal-Hypo always seems to cloud the water - at least temporarily.

So, for all these reasons I'm considering a SWCG. I'm working with the service company to assess if they have the experience and willingness to actually follow a good SWCG management program.