Noob dosing question

Ogus

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I have a newly setup (about 2 months old) 26G reef tank.

Current inhabitants are 3 small hammer frags / 3 small torch frags / 8 different zoas (3 to 10 heads?)
a favia frag, a monti frag and two small toads stool frags along with 2 clown fish.
Currently it is going through ugly stage and my water parameters are

0 Ammonia
0.25 nitrite (was 0 but went up after adding the 2nd clown fish)
0.05ish phosphate
1200ish Mag
400ish Cal
pH at 8.0
Salinity at 1.024
temp at 25C
Nitrate at about 15 ppm
(all tests are done with Nyos kits with nitrite testing done with API)

Corals seem fine.. fish doing great..

but my question is my Mag and Calcium levels drop from 1350is and 450ish after water change to 1200ish and 400ish in about 5 days.

Currently dosing 4 ml TM AFR per day (4 times a day / 1 ml at a time). One time my mag level was under 1200 so I did one shot of
ASF reef shot Mag and it restored the mag level to 1300ish.

I am planning on doing kalkwasser about 50 ml per day during the light out hours.. but should I dose calcium and magnesium instead?
or increase AFR dosing amount and go ahead with kalkwasser plan? I have 4 large dogs that share the space where the tank is and
the soda lime CO2 scrubber isn't doing it's job so to boost pH, kalkwasser came into the idea.

To add, I add a drop of Aquaforest vitality / energy / growth booster food / aminomix each different day per product.
 

rishma

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I don’t see an alkalinity reading. That’s an important measurement. Your 4ml of AFR is adding about 0.25dkh per day.

AFR is adding plenty of magnesium for the calcium and alkalinity it provides. You don’t need to dose more calcium or magnesium separately. The measures drop from 1350 to 1200 in 5 days is likely test error.

You should dose the AFR based on alkalinity consumption. If you do that, it provides plenty of calcium and magnesium.

I use Kalk in addition to AFR. Might be a ok option but it won’t make a big impact on pH because the amount you’ll dose is limited by your alkalinity consumption. I suggest it for your tank at this new stage.
 
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Ogus

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I don’t see an alkalinity reading. That’s an important measurement. Your 4ml of AFR is adding about 0.25dkh per day.

AFR is adding plenty of magnesium for the calcium and alkalinity it provides. You don’t need to dose more. The measured drop from 1350 to 1200 in 5 days is likely test error.

You should dose the AFR based on alkalinity consumption. If you do that, it provides plenty of calcium and magnesium.

I use Kalk in addition to AFR. Might be a ok option but it won’t make a big impact on pH because the amount you’ll dose is limited by your alkalinity consumption. I suggest it for your tank at this new stage.
alkalinity is at 9 pretty steady... I did double testings for cal and mag.. wonder if I made the same mistake 2 times in a row..
 

Randy Holmes-Farley

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I agree. The magnesium change is likely test error or just a salinity change, but it cannot ever be consumed at the rate you suggest.

The calcium depletion is is also very high, and likely isn’t real.

A 100 ppm boost to magnesium takes a huge amount of liquid. You describe it as one shot. Must have been very large.

I'd just use the AFR to maintain alk and stop measuring magnesium and calcium. Check calcium in a few months. :)
 

Gumbies R Us

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Do you know what your daily consumption of alkalinity and calcium are?
 
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Ogus

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I agree. The magnesium change is likely test error or just a salinity change, but it cannot ever be consumed at the rate you suggest.

The calcium depletion is is also very high, and likely isn’t real.

A 100 ppm boost to magnesium takes a huge amount of liquid. You describe it as one shot. Must have been very large.

I'd just use the AFR to maintain alk and stop measuring magnesium and calcium. Check calcium in a few months. :)
o.k. that leaves me at peace.. I would love to be the error myself LOL
 

twentyleagues

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First what is your alk?
Calcium and magnesium test are notoriously incorrect so take that into acct. I have not seen the issues with standard test mine always seem on par with the 2 type of tests I do and they coincide. But a lot of people say the tests are unreliable. If you alk is low bump up your afr if its not I would continue as you are.

Edit lol again work got me. Sorry started to reply before anyone else did but you know it took me 30 min to post that. Carry on nothing to see here.
 

rishma

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alkalinity is at 9 pretty steady... I did double testings for cal and mag.. wonder if I made the same mistake 2 times in a row..

I had to edit my post above because I had a typo. Sorry about that.

Test error with magnesium is so common that many do not tested at home at all anymore (including me). Because I use balanced additives, like all for reef and Kalk, I also don’t test calcium either, except with the occasional ICP.

Calcifying organisms in our tanks reliably follow these ratios… For each 2.8 dKH of alkalinity consumed, about 18-20 ppm calcium and 1-2 ppm magnesium are also consumed. AFR, if dosed to maintain stable alkalinity, provides plenty calcium and magnesium.
 
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Ogus

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First what is your alk?
Calcium and magnesium test are notoriously incorrect so take that into acct. I have not seen the issues with standard test mine always seem on par with the 2 type of tests I do and they coincide. But a lot of people say the tests are unreliable. If you alk is low bump up your afr if its not I would continue as you are.

Edit lol again work got me. Sorry started to reply before anyone else did but you know it took me 30 min to post that. Carry on nothing to see here.
should I stop AFR and measure alkalinity every day for like a week to see? or knowing I add about 0.25 dKH with my AFR per day so if it stays the same it would be about 1 dkH used per day?
 

twentyleagues

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should I stop AFR and measure alkalinity every day for like a week to see? or knowing I add about 0.25 dKH with my AFR per day so if it stays the same it would be about 1 dkH used per day?
No keep dosing it. But check daily and if alk is dropping up your dose a bit each day until you see it stabilize.
 

rishma

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should I stop AFR and measure alkalinity every day for like a week to see? or knowing I add about 0.25 dKH with my AFR per day so if it stays the same it would be about 1 dkH used per day?
I wouldn’t stop your AFR. If you’re dosing four ml per day and the alkalinity stays stable, your consumption is 0.25dkh per day. The 4ml is adding about 0.25dkh total.

If alkalinity is rising, reduce the dose. If falling, increase the dose. But since your consumption is very small, don’t make a dosing change unless you see a steady rise or fall over a period of time, I’d say a week.
 

Randy Holmes-Farley

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o.k. that leaves me at peace.. I would love to be the error myself LOL

Don’t be insulted or even assume it is your fault. Magnesium kits are prone to inaccuracy, so much so that I recommend not testing it in most cases:

 

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