Hey everyone! I posted somewhat recently on this forum about having issues with large dosing quantities and precipitation. The verdict was that it came down to testing.
I have a 60 gallon tank (75ish gallon system) where I dose BRS two part to aid in rapid coralline growth. The tank is 3 and a half months old and has no corals, three fish, a strawberry conch, and a skunk cleaner shrimp (with some trochus snails).
I started using a CO2 scrubber because my condo doesn’t get much fresh air. My pH stays around 7.8-8.0 (which isn’t terrible, but I wanted to get it a bit higher). After adding the CO2 scrubber, my pH sat perfectly between 8.2 and 8.4 all day.
After I began dosing, I couldn’t keep my alkalinity up to save my life. It would drop a lot no matter what I dosed. I got a dosing pump and dosed it to a high flow area of the sump (directly into a power head pointed at my return pump). I dose 24 times a day, and each part is dosed 5 minutes apart. I wanted to see if it was how fast I was dosing. This did not help.
I doubled the dosing quantity, just to keep it stable, but my sand began to turn into a brick! Recall that my tank is really young with a low bioload, and even though I used live sand, I believe the organics within the sand currently do not out compete surface area for abiotic calcium carbonate precipitation.
I tried everything except detaching my CO2 scrubber because I wanted to maintain a higher pH. Having no other option (even after stopping dosing for a few days), I removed the CO2 scrubber.
And behold! Rising and stable alkalinity and calcium! And because I dose soda ash (sodium carbonate), I get a little pH boost, so it’s not quite as low. My pH sits about 7.9-8.0 without it now, but it seems that abiotic precipitation is avoided.
Has anyone else dealt with this issue (CO2 scrubber causing precipitation in the sand)? How long did it take your tank to get to the point that you could raise the pH again without causing sand hardening, or did that ever happen?
I wanted to note that I did try using sodium bicarbonate instead, but I still had precipitation issues at a pH of 8.3. I would love to have my pH of 8.3 and an alkalinity level of 9 dKH, but if I have to settle for a pH of 7.9-8.0 to achieve that alkalinity, I suppose I will! Also, I am sure as I stock the tank more and dirty the sand with some organics, this may subside, but I could be wrong!
I have a 60 gallon tank (75ish gallon system) where I dose BRS two part to aid in rapid coralline growth. The tank is 3 and a half months old and has no corals, three fish, a strawberry conch, and a skunk cleaner shrimp (with some trochus snails).
I started using a CO2 scrubber because my condo doesn’t get much fresh air. My pH stays around 7.8-8.0 (which isn’t terrible, but I wanted to get it a bit higher). After adding the CO2 scrubber, my pH sat perfectly between 8.2 and 8.4 all day.
After I began dosing, I couldn’t keep my alkalinity up to save my life. It would drop a lot no matter what I dosed. I got a dosing pump and dosed it to a high flow area of the sump (directly into a power head pointed at my return pump). I dose 24 times a day, and each part is dosed 5 minutes apart. I wanted to see if it was how fast I was dosing. This did not help.
I doubled the dosing quantity, just to keep it stable, but my sand began to turn into a brick! Recall that my tank is really young with a low bioload, and even though I used live sand, I believe the organics within the sand currently do not out compete surface area for abiotic calcium carbonate precipitation.
I tried everything except detaching my CO2 scrubber because I wanted to maintain a higher pH. Having no other option (even after stopping dosing for a few days), I removed the CO2 scrubber.
And behold! Rising and stable alkalinity and calcium! And because I dose soda ash (sodium carbonate), I get a little pH boost, so it’s not quite as low. My pH sits about 7.9-8.0 without it now, but it seems that abiotic precipitation is avoided.
Has anyone else dealt with this issue (CO2 scrubber causing precipitation in the sand)? How long did it take your tank to get to the point that you could raise the pH again without causing sand hardening, or did that ever happen?
I wanted to note that I did try using sodium bicarbonate instead, but I still had precipitation issues at a pH of 8.3. I would love to have my pH of 8.3 and an alkalinity level of 9 dKH, but if I have to settle for a pH of 7.9-8.0 to achieve that alkalinity, I suppose I will! Also, I am sure as I stock the tank more and dirty the sand with some organics, this may subside, but I could be wrong!