Having trouble raising alk

[Patrick Cox]

I have a roughly 100G primarily SPS aquarium that has been up and running since Feb, 2016. Over the past year or so it has been fairly stable. Over the past year I have been running my Alk around 7.5. I started the tank out with low alk because I initially tried Zeovit but then stopped and never raised my alk. Over the past 6-9 months I have been experiencing some pretty good growth and have had to keep raising my daily dosing. (I use hourly dosing pumps and does ESV products.)

Now all of a sudden my Alk dropped to 6.5 so I started adding some supplemental Alk doses to try to raise my alk level and I can't seem to get the level back up. On top of my daily dosing of 38mm of ESV Alk and CA, I dosed an extra 5 ml per day of Alk with no increase so I tried 10ml per day with no increase and now today I have dosed an additional 20ml of Alk. So now I am wondering if I have a balance issue.

So I just took the following 3 tests...

Alk - 6.6
CA - 385
Mg - 1245

I decided after these tests to also dose 10ml of CA and 100 ml of Magnesium (ESV as well.)

Any thoughts on why I can't seem to get my Alk back up? Maybe there is a problem with my supplement? Is there a way to test the strength of my dosing solution? Do I have a balance issue where one level won't allow Alk to raise? I am not really that well versed on this.

Thanks for suggestions!

 

[bertoni]

Assuming about 70 g of actual water volume, 58 ml per day of B-Ionic Original corresponds to about 2 dKH consumed, which is within normal expectations. Maybe the corals or coralline have picked up in growth? My soft coral tanks went through 2-3 dKH per day for years. I might try dosing 60 ml with measurements before and after the dose, just to be sure the kit is working, but I suspect that you just need to dose more.

 

[Patrick Cox]

Assuming about 70 g of actual water volume, 58 ml per day of B-Ionic Original corresponds to about 2 dKH consumed, which is within normal expectations. Maybe the corals or coralline have picked up in growth? My soft coral tanks went through 2-3 dKH per day for years. I might try dosing 60 ml with measurements before and after the dose, just to be sure the kit is working, but I suspect that you just need to dose more.

Thanks for your reply. I am closer to 90G with my sump so I will try a larger dose and see if that works. I am always cautious about adding too much. But my corals are getting larger so I guess that means they continue to consume more elements.

Thanks.

 

[bertoni]

You're welcome. Good luck!

 

[Patrick Cox]

OK, so this morning I get up and test my alk and it is now 7.2. And as a reminder, for several days I had only been dosing and testing alkalinity. And then last night I tested and then dosed CA and MG, along with another 10 ml of Alk. Values and dosing amounts from last night are above.

Now this morning I find this...

Alk - 7.2
CA - 415
MG - 1330

So, could I have had a balance issue? I feel like I have read that magnesium is required for something and my magnesium was low.

I will keep see where I am at the end of the day today and adjust my dosing pumps from there.

Thanks!

 

[Sugar Magnolia]

Yes, keep mag at about 1350 and you will be able to maintain higher calc and alk values.

 

[bertoni]

Those levels are fine. There's really no such concept as "balance" here. The canonical ocean level for magnesium is around 1270 ppm, so 1320 ppm is fine.

 

[Patrick Cox]

Those levels are fine. There's really no such concept as "balance" here. The canonical ocean level for magnesium is around 1270 ppm, so 1320 ppm is fine.

Thanks. I was at 1245. Could that have been part of my problem?

 

[bertoni]

Not really. I ran with magnesium at 1100 ppm for years because the old Instant Ocean mixed up to that level, and I never had any issues. Eventually, I started bringing the level up out of caution or OCD, I am not sure which, and never noticed a difference.