My non-profit org has an indoor 100,000 gal pool that has been using granular 65% Cal Hypo for decades. I'm looking into switching to liquid Sodium Hypo. Primarily due to the hard water issues that are a pain - Hardness test was over 1200 last week! Refill water hardness is already 250-300. But also because we need to meter chemicals.
We have no local suppliers nearby, but have located a company willing to drive 2 hrs to bring the drums to us. The pool companies can't help much as their systems are not designed for a pool like ours, and I'm not interested in being tied to a branded puck.
So now I'm trying to anticipate cost changes and logistics needs of the different chemical - It looks like we will be using about 5x more bleach daily - a little less than 102 oz of bleach daily compared to 21oz of CalHypo for a 1ppm rise in FC.
It looks like a metering pump running 0.2 GPH (5 gpd) would more than do the job. Line pressure is low as were pumping into a 6" PVC line to the pool - I think we're at 15 psi according to a gauge (if it's working properly...) I'm slightly be worried about throttling down enough do deliver a small amount , perhaps 0.5-1 gpd - 10-20% of it's stated output. Perhaps a 0.1GPH would be a better choice. Some day, if we ever had the funds, it might be nice to have a controller on it, but until then we're all manual. We do already have an outlet that is interconnected to the pump - if circ pump is not running, the CL pump will be off.
Any issues pumping direct from a 30gal drum? To they make a feed-through cap we can use on the drums? Or would we need to transfer to a separate tank/system like a BlueWhite Star III?
Another other option is to keep with the CalHypo and mix into solution ourselves, but I'm assuming that will be a maintenance nightmare trying to keep an agitator running above the tank. Opinions?
Note - We do not use CYA for this pool as rules around Crypto prevent us from doing so inside. No ozone, UV or Cl generator either. Filtration provided by a gravity fed drain to DE filter with the pump providing vacuum for the filter and pushing the water back to the top of the pool.
We have no local suppliers nearby, but have located a company willing to drive 2 hrs to bring the drums to us. The pool companies can't help much as their systems are not designed for a pool like ours, and I'm not interested in being tied to a branded puck.
So now I'm trying to anticipate cost changes and logistics needs of the different chemical - It looks like we will be using about 5x more bleach daily - a little less than 102 oz of bleach daily compared to 21oz of CalHypo for a 1ppm rise in FC.
It looks like a metering pump running 0.2 GPH (5 gpd) would more than do the job. Line pressure is low as were pumping into a 6" PVC line to the pool - I think we're at 15 psi according to a gauge (if it's working properly...) I'm slightly be worried about throttling down enough do deliver a small amount , perhaps 0.5-1 gpd - 10-20% of it's stated output. Perhaps a 0.1GPH would be a better choice. Some day, if we ever had the funds, it might be nice to have a controller on it, but until then we're all manual. We do already have an outlet that is interconnected to the pump - if circ pump is not running, the CL pump will be off.
Any issues pumping direct from a 30gal drum? To they make a feed-through cap we can use on the drums? Or would we need to transfer to a separate tank/system like a BlueWhite Star III?
Another other option is to keep with the CalHypo and mix into solution ourselves, but I'm assuming that will be a maintenance nightmare trying to keep an agitator running above the tank. Opinions?
Note - We do not use CYA for this pool as rules around Crypto prevent us from doing so inside. No ozone, UV or Cl generator either. Filtration provided by a gravity fed drain to DE filter with the pump providing vacuum for the filter and pushing the water back to the top of the pool.
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