modom1207
Active Member
For the last several months, I’ve had a hard time keeping my dKh levels above 6-6.5, even with daily dosing. I think my LFS must’ve changed the salt they use in their premixed saltwater because I tested the water prior to putting it in my tank, and I discovered that it reads right at 7 dkh. Previously, it read at 9 dkh when they were using a better mixture. Thus, I began dosing sodium bicarbonate a few months ago to compensate for this change.
Every day that I dose, I get my levels right to 7. By the next day, they’re back at 6.5. If I wait a few days between doses, they’re down to 6. Meanwhile, my calcium was doing well at 480 in a primarily softie/macro tank, so I saw no reason to dose it. That was until I did a large water change (50%) while moving the tank to a different room, with the added (albeit hopeful) benefit of potentially putting magnesium back to my water in case my mag levels were impacting my dKh. I don’t have a mag test, so I don’t know what my magnesium levels were before the change, but I figured a water change could only bring things closer back to equilibrium at this point anyways. That was a few weeks ago. Immediately after the water change, my calcium levels actually decreased from 480 to 430. I discovered since then that the premixed saltwater only contains about 380 of calcium in it anyways, so it made sense to me that calcium would decrease at that time.
Anyways, a couple weeks go by. I decide to test. On Monday of this week, my calcium was reading really low at 380. My dkh had dropped to 6.5 without sodium bicarbonate dosing. No idea what my magnesium was. I immediately dosed both calcium and sodium bicarbonate. My dkh went up to 7 and calcium crept up to 400.
On Tuesday, I decided that there’s no point in dosing calcium and alk if I know that the reason they’re low to begin with is likely caused by the LFS saltwater mixture. So I went and bought my own “high quality” salt mix, pulled a couple gallons of my aquarium water out (I’m trying to conserve my nitrates so didn’t want to do a water change since I just did one a few weeks ago), added about a half cup of the new salt mix to the aquarium water, mixed it, then put the aquarium water back in and topped off with rodi water so that I wouldn’t swing my salinity. This increased my alkalinity immediately from 7 to 8 dkh. Great! Meanwhile, my calcium levels went to around 420. Awesome! Feeling like maybe with a more expensive salt mixture, I’d have better buffering agents/mag levels/increased calcium, so I thought wouldn’t have to worry about maintaining my levels for a few days at least.
Wrong. I tested this morning (24 hours later). Dkh is back at 7ish (more like 7.25). what the heck? And calcium precipitated out of the water to my back glass and on top of my filter. Now my calcium is back down to 380. ***. What am I missing here? I’m guessing the calcium precipitation occurred from increasing my alkalinity by an entire point within 24 hours. But could something else be causing this?
Here’s what my current params are:
Alk 7.25 dkh
Calcium 380
Mag ??
Salinity 1.026
Temp 78
Ph 8.1
Macros: botryocladia, small cluster of codium, fern caulerpa
Softies: Large colony of GSP, medium sized colony of pulsing Xenia, and small colony of clove polyps
LPS: medium sized 2 headed torch, 1 small hammer, 2 small candy canes, small 3 headed Duncan
Invert: 2 BTAs and 1 RFA, 1 cleaner shrimp, handful of trochus snails, 20ish hermit crabs
Fish: Valentini puffer, clown, couple of cardinals, yellow and shrimp watchman gobies
Tank size: 29 gallon display w a 10 gallon sump
Tank age is 1.5 years
Every day that I dose, I get my levels right to 7. By the next day, they’re back at 6.5. If I wait a few days between doses, they’re down to 6. Meanwhile, my calcium was doing well at 480 in a primarily softie/macro tank, so I saw no reason to dose it. That was until I did a large water change (50%) while moving the tank to a different room, with the added (albeit hopeful) benefit of potentially putting magnesium back to my water in case my mag levels were impacting my dKh. I don’t have a mag test, so I don’t know what my magnesium levels were before the change, but I figured a water change could only bring things closer back to equilibrium at this point anyways. That was a few weeks ago. Immediately after the water change, my calcium levels actually decreased from 480 to 430. I discovered since then that the premixed saltwater only contains about 380 of calcium in it anyways, so it made sense to me that calcium would decrease at that time.
Anyways, a couple weeks go by. I decide to test. On Monday of this week, my calcium was reading really low at 380. My dkh had dropped to 6.5 without sodium bicarbonate dosing. No idea what my magnesium was. I immediately dosed both calcium and sodium bicarbonate. My dkh went up to 7 and calcium crept up to 400.
On Tuesday, I decided that there’s no point in dosing calcium and alk if I know that the reason they’re low to begin with is likely caused by the LFS saltwater mixture. So I went and bought my own “high quality” salt mix, pulled a couple gallons of my aquarium water out (I’m trying to conserve my nitrates so didn’t want to do a water change since I just did one a few weeks ago), added about a half cup of the new salt mix to the aquarium water, mixed it, then put the aquarium water back in and topped off with rodi water so that I wouldn’t swing my salinity. This increased my alkalinity immediately from 7 to 8 dkh. Great! Meanwhile, my calcium levels went to around 420. Awesome! Feeling like maybe with a more expensive salt mixture, I’d have better buffering agents/mag levels/increased calcium, so I thought wouldn’t have to worry about maintaining my levels for a few days at least.
Wrong. I tested this morning (24 hours later). Dkh is back at 7ish (more like 7.25). what the heck? And calcium precipitated out of the water to my back glass and on top of my filter. Now my calcium is back down to 380. ***. What am I missing here? I’m guessing the calcium precipitation occurred from increasing my alkalinity by an entire point within 24 hours. But could something else be causing this?
Here’s what my current params are:
Alk 7.25 dkh
Calcium 380
Mag ??
Salinity 1.026
Temp 78
Ph 8.1
Macros: botryocladia, small cluster of codium, fern caulerpa
Softies: Large colony of GSP, medium sized colony of pulsing Xenia, and small colony of clove polyps
LPS: medium sized 2 headed torch, 1 small hammer, 2 small candy canes, small 3 headed Duncan
Invert: 2 BTAs and 1 RFA, 1 cleaner shrimp, handful of trochus snails, 20ish hermit crabs
Fish: Valentini puffer, clown, couple of cardinals, yellow and shrimp watchman gobies
Tank size: 29 gallon display w a 10 gallon sump
Tank age is 1.5 years
