Alk dropping much faster than calcium

[Shinte122305]

parameters to get started all tested with Hannah and salifert
500 calcium
1500 mag
9 alk
15 nitrates
0.03 phosphates
I use reef crystals bi weekly water changes 25%
75 gallon total volume
60 display 15 sump

After a while I noticed my corals started looking bad and one of my torch corals melted away I checked all parameters and everything was high just like above except alk was at 7.

I slowly raised alk dosing it with brs 2 part but just the alk one atleast 1 dkh a day until it’s been at 9-10.

I’m having to dose alk every day about 1 dkh or more to get it to stay between 9-10. Calcium stays stable 480-500 im assuming it’s stable from water changes and the Kalkwasser in my ATO.

I don’t understand why alk keeps plummeting I thought calcium and alk where suppose to go down evenly.

My other issue is PH, the tank is in the middle of my house so I can’t run a tube outside for the skimmer so I use a C02 scrubber but it runs out in less than a week and PH drops like crazy 7.8 during the day and 7.6 at night if the scrubber starts running out...... this is with a full dose of saturated Kalkwasser. Idk what’s going on lol

 

[Mike Ducharme]

parameters to get started all tested with Hannah and salifert
500 calcium
1500 mag
9 alk
15 nitrates
0.03 phosphates
I use reef crystals bi weekly water changes 25%
75 gallon total volume
60 display 15 sump

After a while I noticed my corals started looking bad and one of my torch corals melted away I checked all parameters and everything was high just like above except alk was at 7.

I slowly raised alk dosing it with brs 2 part but just the alk one atleast 1 dkh a day until it’s been at 9-10.

I’m having to dose alk every day about 1 dkh or more to get it to stay between 9-10. Calcium stays stable 480-500 im assuming it’s stable from water changes and the Kalkwasser in my ATO.

I don’t understand why alk keeps plummeting I thought calcium and alk where suppose to go down evenly.

My other issue is PH, the tank is in the middle of my house so I can’t run a tube outside for the skimmer so I use a C02 scrubber but it runs out in less than a week and PH drops like crazy 7.8 during the day and 7.6 at night if the scrubber starts running out...... this is with a full dose of saturated Kalkwasser. Idk what’s going on lol

I wouldn't sorry about chasing PH too much.. Alkalinity and calcium don't always get consumed evenly, from my experience i always have to dose more alk than calcium. If you're still worried about the calcium being off you can test at home then bring a sample into your LFS for cross referencing. It could also be a faulty test kit causing a misread.

 

[Shinte122305]

I just find it nuts how my alk drops and how my ph is constantly low. It’s not that I’m chasing ph but if I don’t put a scrubber my apex shows that it’s dropping to 7.5 ph during the night and all my corals look horrible when that happens. I calibrated my probe just to be sure and same thing.

I don’t mind keeping up with the c02 scrubber to keep ph in the 7.8 range I just find it all a bit odd.

 

[Randy Holmes-Farley Verified Community Expert]

Alk depletion is usually from 0.3 to 4 dKH per day. 1 dKH is certainly not unusual, even in a soft coral tank.

The expect calcium drop in your tank will be quite low, and as a percentage of the levels, the calcium drop per day is far lower than alk, ALWAYS. About 18-20 ppm calcium for each 2.8 dKH. Your kit cannot reliable detect a few ppm drop in calcium.

It's not odd to have low pH either, and the tigheter (newer) your home the lower the pH is likely to be due to excessive CO2 in your home air. There are many options if the pH is accurate (what device are you using?) A scrubber, growing macroalgae, using limewater or other very high pH alk additive, outside air to a skimmer inlet, etc.

 

[BestMomEver]

I just find it nuts how my alk drops and how my ph is constantly low. It’s not that I’m chasing ph but if I don’t put a scrubber my apex shows that it’s dropping to 7.5 ph during the night and all my corals look horrible when that happens. I calibrated my probe just to be sure and same thing.

I don’t mind keeping up with the c02 scrubber to keep ph in the 7.8 range I just find it all a bit odd.

I had the same problem.... I added a CO2 scrubber and within 2 days the pH was up and other elements became more stable. At that point I could start dosing more accurately. Before that my test results were all over the place. After a few months I tested...

440 calcium
dkh 9.0
Magnesium 1360
pH 8.2

 

[Randy Holmes-Farley Verified Community Expert]

FWIW, low pH will reduce the consumption demand for calcium and alkalinity, but should not otherwise contribute to instability in these values.

 

[Shinte122305]

Thanks for the replies! I’m using a BRS c02 scrubber and their color changing resin. I’m also using brs Kalkwasser in my ATO, fully saturated in my 5 gallon jug.
Honestly the alk drop has been manageable with my daily dose of alk it seams I caught it on time and it’s holding at 9.3 today. I’m using Hannah tester for alk.
Calcium doesn’t budge 480 again I tested with salifert.
I’m trying to figure out a way to run a tube across the wall to outside because the scrubber runs out within 4-5 days and ph drops a lot. 7.8-8.0 with scrubber and then I start seeing 7.7 during the day after 4-5 days and I have to refill scrubber. It’s getting very expensive to refill. Ima work on a way to get the skimmer breathing outside air ASAP.
And Randy says low ph reduces consumption demand dang lol. Thing is when my torch melted I had stopped using the scrubber and I didn’t realize the alk was so low so I don’t know if it was the ph that killed it or the 7 alk. Anyway sima fix both

 

[Randy Holmes-Farley Verified Community Expert]

Alk steady at 7 dKH won't kill a coral. That's typical to a tad higher than in the ocean. sudden drops aren't good, however.