Recovering from a faux pas regarding the salt mix used when making SW for my AWC. Being the first AWC system I setup, I did not think this through, and just continued using my normal 'manual' water change salt mix, Red Sea Coral Pro. This has been a great salt mix for me, and I've used it for many years. But for AWC storage, not a good idea.
After just a few months of AWC'ing with this salt, my storage container had a good deal of precipitates encrusted on the bottom. It also left a little sandy grit as well. I thought, no problem, I would just clean the container every few months, but then noticed that the lines from my container to my DOS also had precipitates.
Because of this thin white layer on the inner wall of my RODI tubing, I believe the amount of SW pulled into the DOS during my AWC was affected, because the SW could not fill the entire inner diameter of the tubing as it was partly caked with precipitates. So I believe I was pulling in slightly less SW than I was taking out with my WW line, which in turn caused my ATO to replace the difference, leading to a gradual reduction in salinity. Both DOS lines were calibrated properly and tested several times, so I'm pretty sure it's not a DOS issue.
I finished running a vinegar solution through the AWC lines, and that took out quite a bit of precipitates. I took the lines apart to visually investigate, and now they are squeaky clean. I also soaked my SW storage bin in the vinegar solution overnight, and cleaned it out, and rinsed with RODI today. Now the container is squeaky clean too.
Everything is good to go for my SW mixing day tomorrow. I will be starting fresh with Tropic Marin Pro, which has gotten great reviews not just for mixing and storage, but also for the results seen in the reef. It will mean that I have to adjust my alk dosing, but I'd rather do that than gunk up my AWC lines. Unfortunately, this salt is about $25 more per bucket, but it will be worth it if it resolves the above issues.
Anyway, thought I'd share, and perhaps prevent someone from making the same mistake.
Would be interested to hear from anyone else who has had this problem, and what salt mix they currently use.
After just a few months of AWC'ing with this salt, my storage container had a good deal of precipitates encrusted on the bottom. It also left a little sandy grit as well. I thought, no problem, I would just clean the container every few months, but then noticed that the lines from my container to my DOS also had precipitates.
Because of this thin white layer on the inner wall of my RODI tubing, I believe the amount of SW pulled into the DOS during my AWC was affected, because the SW could not fill the entire inner diameter of the tubing as it was partly caked with precipitates. So I believe I was pulling in slightly less SW than I was taking out with my WW line, which in turn caused my ATO to replace the difference, leading to a gradual reduction in salinity. Both DOS lines were calibrated properly and tested several times, so I'm pretty sure it's not a DOS issue.
I finished running a vinegar solution through the AWC lines, and that took out quite a bit of precipitates. I took the lines apart to visually investigate, and now they are squeaky clean. I also soaked my SW storage bin in the vinegar solution overnight, and cleaned it out, and rinsed with RODI today. Now the container is squeaky clean too.
Everything is good to go for my SW mixing day tomorrow. I will be starting fresh with Tropic Marin Pro, which has gotten great reviews not just for mixing and storage, but also for the results seen in the reef. It will mean that I have to adjust my alk dosing, but I'd rather do that than gunk up my AWC lines. Unfortunately, this salt is about $25 more per bucket, but it will be worth it if it resolves the above issues.
Anyway, thought I'd share, and perhaps prevent someone from making the same mistake.
Would be interested to hear from anyone else who has had this problem, and what salt mix they currently use.