Can dosing MAG raise dKH?

[amazongb]

Here are my parameters from a week ago:

NO3: 8
PO4: .03
Mag: 1200
KH: 7.4
CA: 420

I then dosed 10ppm of MAG daily for 7 days to raise to 1270. I'm also dosing 1.5ML of Seachem Flourish to keep PO4 at .03/.04. I use Neptune DDOS to spread doses throughout the day.

Parameters today:
NO3: 8
PO4: .03
Mag: 1270
dKH: 7.9
CA: 420

The only thing I dosed all week was mag, yet dKH elevated to 7.9.

Total water volume is 120 gallons.

I use a Hanna Alk checker and tested twice. Reagent expires 5/20.

 

[Billldg]

Dosing Mag doesn't raise you alk, it will keep you alk and cal from participating. I would check you hanna vials, do you clean them with their cleaner after every use. A .5 raise in Alk isn't that much when you take into consideration of the margin of error in the hanna checker.

 

[Billldg]

I keep my Mag at 1500 ppm to keep my tank from precipitating. I also have a 120 gal tank.

 

[Billldg]

Did you check your PH before and after also, it would effect it more. Higher PH allows you frags to use more Alk and Cal.

 

[amazongb]

Did you check your PH before and after also, it would effect it more. Higher PH allows you frags to use more Alk and Cal.

My PH fluctuates daily between 8.09 and 8.24. Just puzzled on how dKH would rise on its own..

 

[amazongb]

Dosing Mag doesn't raise you alk, it will keep you alk and cal from participating. I would check you hanna vials, do you clean them with their cleaner after every use. A .5 raise in Alk isn't that much when you take into consideration of the margin of error in the hanna checker.

Yes, I clean them very well with RODI water, my vials looks brand new when I use them. I also rinse my vials with RODI water prior to use..

 

[Earl Karl]

Could be tester issue, the margin of error is normal.

How do you dose Ca and Alk?

 

[Randy Holmes-Farley Verified Community Expert]

Did you check your PH before and after also, it would effect it more. Higher PH allows you frags to use more Alk and Cal.

magnesium dosing won’t impact pH or alk, unless you dose some strange chemical.

 

[Billldg]

You may have been precipitating a little with the mag at 1200, and now that the mag is up a little you aren't as much thus the .5 dkh rise in a week. I would monitor it and see what it is in another week. I would also raise your mag to 1380 as that seems to be the middle ground. I keep mine at 1500 because their isn't ill effect and I wanted to make sure I wasn't precipitaiting.

Also, the vials should be cleaned with either their solution, or some sort of alcohol. I use their solution, but to me it seems to be a alcohol cleaner of some sort as you can smell it. I also used RO/DI water at first to clean the vials and found out the hard way that it doesn't clean it properly by itself.

 

[Randy Holmes-Farley Verified Community Expert]

My PH fluctuates daily between 8.09 and 8.24. Just puzzled on how dKH would rise on its own..

it didn’t.

 

[Billldg]

magnesium dosing won’t impact pH or alk, unless you dose some strange chemical.

I referred to PH effecting the Alk consumption, not mag effecting PH.

 

[Randy Holmes-Farley Verified Community Expert]

I referred to PH effecting the Alk consumption, not mag effecting PH.

ok.

 

[amazongb]

Could be tester issue, the margin of error is normal.

How do you dose Ca and Alk?

I'm not dosing either because my tank is LPS dominant and water changes seem to be keeping everything within range..

 

[Earl Karl]

Wat salt do you use? Salt with higher alk can alter ur tank's alk.

 

[amazongb]

magnesium dosing won’t impact pH or alk, unless you dose some strange chemical.

I'm only dosing Seachem Flourish and Mag, nothing else.. I guess it's a testing issue, which I'll work on..

 

[Randy Holmes-Farley Verified Community Expert]

I'm not dosing either because my tank is LPS dominant and water changes seem to be keeping everything within range..

then magnesium will be fine too. It will be exactly what Is in your salt mix.

 

[amazongb]

Wat salt do you use? Salt with higher alk can alter ur tank's alk.

I'm using Tropic Marin Pro. The test I conducted was between water changes, so there wasn't a water change that would've raise alk.

 

[Earl Karl]

Ye I would assume it's testing, considering TM Pro only has 7 dkh.

 

[amazongb]

You may have been precipitating a little with the mag at 1200, and now that the mag is up a little you aren't as much thus the .5 dkh rise in a week. I would monitor it and see what it is in another week. I would also raise your mag to 1380 as that seems to be the middle ground. I keep mine at 1500 because their isn't ill effect and I wanted to make sure I wasn't precipitaiting.

Also, the vials should be cleaned with either their solution, or some sort of alcohol. I use their solution, but to me it seems to be a alcohol cleaner of some sort as you can smell it. I also used RO/DI water at first to clean the vials and found out the hard way that it doesn't clean it properly by itself.

I will try the alcohol cleaning and report back. Thanks for that tip!

 

[eea60123]

I’m not a chemist but the magnesium alters the calcium and alkalinity bond. It may be that your magnesium levels are not raising your alkalinity but keeping too much from bonding with calcium which could or could not raise your levels.