- Jan 26, 2011
- 40
I thought I'd talk a bit about the results of all this.
First, there hasn't been any change to Muriatic Acid (HCl), except that the concentration has dropped in the stores. We used to be able to buy >30% mixes anywhere we went, but now the big box stores carry stuff that is less than 15%. In my location, Leslie's and Ace Hardware carry 29%. Calcium Carbonate will react just fine when hit with the 15%, and even more so with the 29%, but Calcium Sulfate won't. Note that Calcium Sulfate will dissolve in HCl, but it takes longer and doesn't boil, so you may not know it is happening. That's why one should leave a chlorine generator in the acid bath for some length of time to actually get the stuff off. Personally, I seldom use an acid bath on the chlorine generator; I use a lower power power washer (1200-1400 psi) to clean the thing because I can't help but think the acid wash will shorten the life of that expensive part. The power washer also does a pretty good job on the cartridge filter elements I have if I'm careful not to blow a hole in them (you only make that mistake once).
I couldn't find a way to get the Ca out of the pool chemically. That left changing the water, but my CH of the available water didn't seem to make that a good solution. I'd just be back in the same situation in a short time. I've been told, but haven't proven it yet that peak evaporation in my area can reach 300 gal/day. Now, I have no data on how big a pool that is, how deep it is or how warm the person kept the pool, so that is just rumor. However, the evaporation rate is high in the summer; it gets to 135F in the sun (yes, I measured it) at times here so evaporation has to be high. Remember, the temperature in the sun is considerably higher than the air temperature. So I had a reverse osmosis machine come out and treat the water. My loss was in excess of 2000 gallons from a 10,000 gallon pool, but that was because the water was so high in CH that it took a lot to purge the membrane in the filter. As the process progressed there was a visible decrease in the waste water produced so it was obvious that things were getting better as the water was cleaned up.
I had the guy (over his objections) take the pool down as far as we could get it. My measured CH was around 150 and the guy told me that that would cause problems. My pool is pebble tek and tile with totally plastic fittings everywhere. I wasn't worried except where the tile grout was exposed at the top of the pool. This turned out to be a wise decision because it softened and eventually dissolved the calcium line at the waterline of the pool. Yes, I noticed it was getting soft and hit it with the power washer to force a lot of it off, then raised the water level to cover the remaining line. Over a couple of days it softened it as well and a little scraping with a stainless steel putty knife got 95% of the rest. I'm still waiting for the tiny bit remaining to dissolve and then I'll take the water level back down. I'm sure this line will come back over time, but I know how to fix it now. Yes, my CH level is still low, but I expect the desert water and dryness to take care of that problem for me; most likely sooner than I want. So I saved a considerable amount of work scraping or money having the pool blasted with those little glass beads to clean off the calcium line.
This episode probably cost me around $600 or a little over that to complete, so weigh the factors carefully making your own decisions how to proceed.
And, have fun.
First, there hasn't been any change to Muriatic Acid (HCl), except that the concentration has dropped in the stores. We used to be able to buy >30% mixes anywhere we went, but now the big box stores carry stuff that is less than 15%. In my location, Leslie's and Ace Hardware carry 29%. Calcium Carbonate will react just fine when hit with the 15%, and even more so with the 29%, but Calcium Sulfate won't. Note that Calcium Sulfate will dissolve in HCl, but it takes longer and doesn't boil, so you may not know it is happening. That's why one should leave a chlorine generator in the acid bath for some length of time to actually get the stuff off. Personally, I seldom use an acid bath on the chlorine generator; I use a lower power power washer (1200-1400 psi) to clean the thing because I can't help but think the acid wash will shorten the life of that expensive part. The power washer also does a pretty good job on the cartridge filter elements I have if I'm careful not to blow a hole in them (you only make that mistake once).
I couldn't find a way to get the Ca out of the pool chemically. That left changing the water, but my CH of the available water didn't seem to make that a good solution. I'd just be back in the same situation in a short time. I've been told, but haven't proven it yet that peak evaporation in my area can reach 300 gal/day. Now, I have no data on how big a pool that is, how deep it is or how warm the person kept the pool, so that is just rumor. However, the evaporation rate is high in the summer; it gets to 135F in the sun (yes, I measured it) at times here so evaporation has to be high. Remember, the temperature in the sun is considerably higher than the air temperature. So I had a reverse osmosis machine come out and treat the water. My loss was in excess of 2000 gallons from a 10,000 gallon pool, but that was because the water was so high in CH that it took a lot to purge the membrane in the filter. As the process progressed there was a visible decrease in the waste water produced so it was obvious that things were getting better as the water was cleaned up.
I had the guy (over his objections) take the pool down as far as we could get it. My measured CH was around 150 and the guy told me that that would cause problems. My pool is pebble tek and tile with totally plastic fittings everywhere. I wasn't worried except where the tile grout was exposed at the top of the pool. This turned out to be a wise decision because it softened and eventually dissolved the calcium line at the waterline of the pool. Yes, I noticed it was getting soft and hit it with the power washer to force a lot of it off, then raised the water level to cover the remaining line. Over a couple of days it softened it as well and a little scraping with a stainless steel putty knife got 95% of the rest. I'm still waiting for the tiny bit remaining to dissolve and then I'll take the water level back down. I'm sure this line will come back over time, but I know how to fix it now. Yes, my CH level is still low, but I expect the desert water and dryness to take care of that problem for me; most likely sooner than I want. So I saved a considerable amount of work scraping or money having the pool blasted with those little glass beads to clean off the calcium line.
This episode probably cost me around $600 or a little over that to complete, so weigh the factors carefully making your own decisions how to proceed.
And, have fun.